I got a few minutes to play with the latest build of Windows Vista last night. I've only just installed it, so keep in mind these are just first impressions. They may change.
The installation is now graphical from the very beginning. A nice change. The installation is also nicely minimal. You pretty much just set it to install and then let it do it's thing. You don't need to click so many boxes anymore. It does a lot of this stuff automatically. I like this newer, simpler install. The only thing I would change is the progress bar on the bottom. The install takes a long time. It often seems as if it's not doing anything. For a while there I thought it got stuck. The installation needs a bit more 'confort UI' to ensure you that it is actually doing something. Maybe a 'time left to complete' or something that counts down...
The Control Panel is completely rearranged. I actually kind of like this arrangement. It seems to make more logical sense than previous versions of Windows.
The UI is interesting. I like most of the changes they have done. They finally got rid of the word "Start" from the menu button in the lower left corner... I always thought that was a really stupid design. I like this change. They made the taskbar default to a shaded black color... I'm not sure about this one. The minimize, maximize and close buttons in the upper right hand corner of a window look different. I'm not sure I like this look. I like how the buttons kind of light up when you hover over them though. Many of the windows now kind of 'expand' out when you open them. They don't just pop onto the screen. This is an interesting effect that I kind of like. I haven't played with the UI too much yet, but it does look like they've enhanced the 'snazzy' effects quite a bit. I'm not sure it's up to the Mac level of snazzy effects, but it's an improvement.
I haven't been able to try out Internet Explorer yet. Apparently it didn't detect my motherboard's network card properly and install the drivers. I'm going to have to try to do that manually.
It is buggy though. It seems to have some trouble with going into and out of Sleep mode. When I put it to sleep, it went to sleep very rapidly (nice!). But when I brought it back from sleep mode, it seemed to lose the mouse. I was forced to use the keyboard from that point on. Once I got back from sleep mode, I actually tried to shut it down and it seemed to get stuck in the middle of shutdown.
All in all, my first impression is that this new Windows looks promising. I'll have to play with it some more to see how stable it is and how well things work.