Thanks for posting those, Nos! I like the new look but it's not really the look that I am excited about.
I disagree that the advanced that Microsoft are making are meaningless. Most applications aren't 64 because there aren't enough users with the capability. With the advent of 64bit/128bit computing, Windows has to provide the services first before software companies will make the move. It doesn't have to be that way but it makes sense from a modern computing standpoint. You can't lead the platform from the software.
The backend of Longhorn is what I'm looking forward to and it's not dumbing down or a small advance. The XP/2000 file system is build upon NT technology - fine for the day it was created in and certainly better than the FAT32 dog that was implemented in Win 95/98. However, this sort of file system does not cater for a system that has huge amounts of very fast memory and a set of files that can be indexed in many different ways. That's why Longhorn is built on a next generation system: WinFS.
Furthermore, the core of Windows XP/2000 is massive and mostly pointless. Backward compatibility was a requirement (understandably) without the need for emulation (a program running within a program). However, with the speeds of modern processors, you can get away with emulation. This allowed Microsoft to rewrite the core.
Finally, Longhorn is built upon a firm foundation of .NET. For those non-programmers out there, it's a programming system with all the standardisation of Java with the flexibility of the 'Visual languages' and will allow much smoother, bug-free programs that won't eat memory at the drop of a hat.
Only time will tell whether these advances are worthwhile but from my initial findings, I like to think they are.