I took the plunge and installed Vista beta 1 on one of my computers at work (the one that I don't use to build Office). I only used it for a couple minutes before heading home—I was summoned to play Warcraft for a bit—but I was pleasantly surprised with the performance. It's a 3 GHz machine with a puny GeForce FX 5200, and it seemed to run very nicely with all of the glass effects turned on. I was kind of afraid that it would be really bad on a machine with a low-end video card like that, and would be sluggish in general just because it's a beta, but it really seems like it will be quite usable. Sometime this weekend I need to head in and install Office and Visual Studio and Firefox and StickyPad and all of the other typical goodies on it, so I can, you know, do my job. In doing that I should get a much better feel for how it runs.
The installer for Vista is pretty nice. You enter your product key, pick a computer name, and pick a partition to install to, and that's it. You come back half an hour later and you're at the Vista desktop. It seems to be quite a bit more streamlined than XP's installer, and at no point was I treated to a text-only screen or had to wait five minutes while drivers loaded from the DVD.
Mmmmmm... Windows Vista beta 1, Visual Studio 2005 beta 2, and pre-alpha Office 12 are all soon going to be running on the same machine. Let's see how that goes.
Update: I've now used Vista for a couple hours on my work machine, and my initial observations have been confirmed. Aero Glass is definitely slower than the classic theme or Windows Server 2003, at least with this crappy video card. It's just a little faster than the point where I'd be really annoyed; it's "acceptable." Now, if it ran like this at home, with a Radeon X800XT PE, I'd be quite upset. I haven't run into any major annoyances yet. My main problem, which I was aware of before switching, was that Windows Explorer doesn't have List view anymore, which is the view I used 98-99% of the time (the other 1-2% being Details). You can still use Small Icons, which is the same as List, except the icons sort horizontally, which just isn't the way that humans read columnar data. Have these people ever seen a newspaper?