The Seibertronians are better known as androids, and in a nutshell, they largely either are indifferent to humanity, or they dislike us. Fortunately for humanity, these robots are rather fond of things like nations, organizations, large industrial bases, and all of the other things that humans make and keep running. This would be more of a concern if there were more of them. Thankfully, true Seibertronians are rare in number.
What is a Seibertronian?
Not all androids are Seibertronians. To be a Seibertronian an android must demonstrate true sentience and self awareness. The technology that causes robots to become self aware isn't understood, nor is the effect easily repeatable. The core of the android is it's brain. This neo-cortex is pure machine, but designed to function like the lobes of a human brain. Many parts in a neo-cortex are interchangeable with the parts in the artificial brain used by brain transplantees. Each neo-cortex gets one chance to become sentient, when it is powered up the first time. Either the 'spark' of intelligence stirs in the lumps of metal and synthplastics suspended in a classified fluid or it doesn't. The neo-cortices that don't spark are sent on to be used in menial labor robots, and public service robots.
The appearance of Seibertronians is highly variable. Most start in standard android chassis' but this doesn't last long as they quite quickly will modify their new 'carapace' or 'frame' to suit their jobs, aesthetic sense, or raison d'etre. Military 'bots will have increasingly large and powerful bodies, while infiltrators and negotiators will have more humane looking bodies. One thing in common, is that few keep their human appearance, and will make it obvious that they are machines and not humans. The most gruesome aspect is manually removing the latex-silicon shell that wraps around most androids bodies to hide their gleaming steel and ceramic parts. Most will adopt fully mechanical bodies, rather than skeletonizing themselves.
Humans require no greater purpose than the twin biological drives: fornicate and eat. Seibertronians are much more involved, as their existence isn't ruled by hormones and biological impulses. The seeking of a greater purpose, a reason for being, drives many Seibertronians.
Explorer: the world is full of experiences beyond the pursuit of sex and food. Explorers are drawn to go places where no one has gone before. Explorers find new things and bring them back, or they go places that most humans will never see beyond a holovid. Not surprisingly many Seibertronians are drawn to space and space exploration.
Scientist: there is no greater pursuit than the seeking of knowledge. The Scientist explores from the laboratory or observatory, taking in data, and processing it. There are few fields that Seibertronian scientists are not able to quickly master with their considerable intellects. They do generally avoid social sciences, history and the like. They prefer hard sciences and retain their dislike of humanity, unless it is in the context of basic biomechanics, or biochemistry.
Soldier: the reason for existence is the protection and promotion of the greater organization, be it a state, a megacorporation, or other large and organized group.
Creator: Seibertronians can be prolific builders, creating buildings, electronic programs, more robots, weapons. They echo their own creation through the tireless work of their own hands.
Servant: There are certainly servile Seibertronians, though this service is generally only given to other deemed superior Seibertronians. While some are simply cybernetic sycophants, many have a secondary raison d'etre such as being a servile soldier, or servant laborer.
What a Seibertronian is Not
Seibertronians are not Super Computers. Their intellect is limited to what the processors and memory banks inside their neo-cortex can hold. While they are by no means dimwitted, their associated skills are limited to a reasonable degree, if exceptional degree. While mechanical, Seibertronians also develop emotional response systems, defined personalities, and can engage in abstract concepts like imitation, intentional deceit, creating art and appreciating things like music, patterns, and other decidedly human things. That being said, they are just as capable of having psychological issues, ineptitudes and suffer from things like negative emotions, bad taste and bad behavior.
Seibertronians are also not Transformers, despite the name. They are closer in nature to the AutoReivs of Ergo Proxy, Soong Androids from Star Trek, or the Terminators from the same named franchise. The main difference is that the Seibertronians are much more willing to alter their own appearance and are not bothered with concepts like self image. To them,a body is nothing more than a complex interface system that they use to access the three dimensional world, to be modified or replaced as the mood takes them. A Seibertronian can use a humanoid droid type body, then, have it's neo-cortex placed into the chassis of a droid tank and continue on as if they had always been a droid tank. Many Seibertronians will spend time custom building their own series of bodies to use as situations demand.
There are dozens of reasons to not allow this, but there is no non-game balancing reason that a Seibertronian intellect could not decide to use a battlemech as it's body. The Limited AI that controls the giant war machine would be configured to communicate electronically with the neo-cortex wired into it, functioning as a sort of second-subconscious that controls the massive body. An 80 ton war machine could start exhibiting the physical mannerisms of the Seibertronian that uses the robot as it's shell. Seibertronian mecha are no longer required to make piloting rolls, can use all of the martial arts skills of the Seibertronian that controls it, and are naturally and horrifically accurate with their weapons.
Seibertronians are not Terminators. While they dislike humanity, it isn't a genocidal dislike. It can manifest into violence against humans, but the Seibertronian phenomenon is no easier for them to replicate, so their ability to replace their numbers is just as limited as human ability to create new Seibertronians. Their neo-cortices are vulnerable to computer viruses, EMPs are as lethal to them as nuclear blasts are to humans. The number of actively hostile Seibertronians is contained by the number of apathetic or indifferent members of their race.
Boy Bots and Girl Bots
Seibertronians do display certain idiosyncrasies and outward manifestations of gender, despite having no biological reason. Their minds and personas were built from models and replicas of human minds, and retain the manifestation of being male or female. This is less common in older and more developed psyches, with their mechanical shells becoming less influenced by human appearances and more defined by their raison d'etre. A military minded Seibertronian is not going to keep using a civilian type 6 Personal Escort body (Stepfordco BlondeBombshell) when it can replace the soft squishy android body for the thickly armored body of a Wolverine main battle mech. Listing the features that define male and female Seibertronians would be a waste of time, for every Seibertronian that runs around in a pink lithe girlbot body, there is one that is inhuman, bristling with strange devices and weapons. Likewise for male Seibertronians. Their interaction with the world is highly variable, and it is easier to simply apply a gender to the mind behind the machine.
Boys and girls can do the same thing, but it comes from completely different reasons and rationalizations. A man with a rifle and a woman with a rifle can functionally do the exact same thing, with a completely different set of emotions. This can translate over to the Seibertronians with strange outcomes, such as a soldier type being a very caring and femininely emotional machine, or a builder type could be building new robots in a motherly function, but treat them with the rough and demanding manner odd and out of sort for a caregiver. The image that came to my mind was the Decepticon Shockwave. A giant purple robot cyclops noted for it's cold and calculating nature. Assigning a gender to Shockwave can completely change the nature of the character to frightening effect. The robot is normally portrayed as 'neutral' and being more machinelike that it' contemporary Decepticon companions. When male is applied, the source of his emotional void comes into question, trauma from war? dispassionate hatred? The cold and calculating attention to detail and non-emotional focus of the scientist? This can go the other way and making the giant purple robot female IMHO makes it even more disturbing. Imagine a coldly angry woman, and then replace her left arm with a fusion cannon. If you're not scared, you should be.
Seibertronian versus Artificial Intelligence
Artificial Intelligence, Limited Artificial Intelligence, Synthetic Intelligence exist in the setting of the Cosmic era. Functionally these things can act in similar roles to Seibertronians, and vice versa. The difference between these types of machines and a Seibertronian is a matter of hardware. AI, and LAI are based on computer mainframes and 'Thought Algorithms' rather than having a neo-cortex that is modeled on a human brain. AIs and LAIs can have motivations, goals, plans and the like, but they do not have emotional feedback and response systems. The AI can act happy, but it is imitation, whereas the Seibertronian can experience happiness. This is a point of contention between the two types of machines. The AIs and LAIs consider the Seibertronians to be the worst aspects of humanity (emotionalism, irrational behavior, sentimentalism) and the weakest aspects of machinery (predictability, static development, Logic issues) rolled into one undesirable package. Why waste resources making mechanical humans when humans are fairly capable of replicating themselves biologically. Seibertronians consider the AIs and LAIs as throwbacks and archaic machines based on dated machine architectures, the computer plant to their mechanical animal.
Both sides have significant advantages and disadvantages. The Seibertronians are personally mobile, and can imitate humans, control machines with exceptional skill, and can literally walk up to the mainframe housing an AI or LAI and unplug it. The AIs have staggeringly more computer power and a match up between the two in terms of control and programming the AIs win by an embarrassing margin. They are on two different scales. A Seibertronian can pilot one machine, an AI can remote pilot dozens, hundreds. The AISC Argus, a military machine, can coordinate a naval armada, two airwings, and an army group of drone tanks and drone mecha. LAIs are more numerous than Seibertronians, and like their counterparts, can control a vehicle with ease and great skill. LAIs are also mass produced and outnumber the Seibertronians by a wide margin.
The Seibertronian isn't the only intelligent robot in the Cosmic Era, and in terms of ability, they are not the best equipped or most capable. They are much closer to humans than any other machine. Like us, they are fully capable of doing idiotic things, or be motivated by more base interests. In the Transformers series, the titular transformers rarely act like machines, and the ones that are non-emotional are exceptional because of this lack of emotion. They rant, they rave, they perform heroic acts of self sacrifice, acts of blindness and intentional cruelty, they graduated from the Stormtrooper Marksmanship academy, and make sometimes brutally obvious mistakes. It is my opinion that this comes from not the setting and core material, but from the writers of the series. Rather than projecting human characteristics onto machines, the Seibertronians are based on machines characteristics that have been projected onto humans.
Given their inhumanity tied into their innate human mode of thought and emotional response, Seibertronians are exploring who they are, what they are, and this is why their raison d'etre is central to their functionality. A machine without a purpose doesn't do anything, and people who do nothing are decidedly unhappy. Finding their purpose is a vital function of the Seibertronian mind, and as a race, they are looking towards creating their racial identity, and unlike many robots in sci fi and fantasy, the Seibertronians do not strive to be more human. Why should they? Humans have by this point proven themselves to be easily distracted, easily addicted and controlled, easily manipulated, and to the last, mortal.
Seibertron and Primus
the Seibertronians have a concept of Heaven and the afterlife, as well as understanding dimensional physics. While they are unable to use things like parapsychic abilities (because what's the next step? psychic flying robots that turn into dragons?) they are able to comprehend them. The functionality of the Seibertronians comes from the neo-cortex. The neo-cortex itself is derived from arcanotechnology, and that realm of science and mysticism is drawn from dark inspiration that finds it's source in the River of Sorrow. The Seibertronians, like all the other expressions of dimensional and arcanotechnology are innately and inescapably tainted by spiritual corruption. The degree of taint is variable, some are more affected than others. The more corrupted the individual has become, the more like an absolute machine they think and act, while those that cultivate ideals of compassion and generosity and generally positive things are less tainted and much less affected.
The Seibertronians recognize a racial gestalt, which they refer to as Primus. They do not believe that there is a metaphysical and supernatural origin to their race, a machine god. Rather the human mind and psyche is seemingly predisposed to believing in gods (Elder gods, the fey gods of man, the dread Cthulhu) and unlike man the Seibertronians know where they came from and what their purpose is. Man created them, in the factory crucibles, to be servants, soldiers, companions. There is no lofty greater purpose. But possessing a true intellect and personality, they seek greater truths that have eluded man, that man himself still seeks in the Cosmic Era. Primus serves as their referential deity. Sometimes this is done in a satirical fashion, making fun of mankind and human religion, other times it is a function to differentiate the Seibertronians from Humans. Human detractors of AI and Seibertronians call Primus Robo-God and as one of the prime reasons the machine impersonator demons should be destroyed.
An interesting argument can be made that Seibertronians are innately flawed, tainted as they are by the river. Robot sin would be a different thing that human morality, and that faith in something like Primus could possibly lead to salvation or grace (protection from the taint, ability to exist without the negative influence of their corruptable essence) but that is as far as I am going to go into that, here.