SP1 fixes a lot of issues of Vista, including the transfer issues you mentioned in another thread.
Also, to be fair, I've generally found computers, in general, regardless of OS, to be worse in a network setting. One example are the Macs at my School. I believe they're G5 iMacs or early Intel iMacs. Well, anyway, they're running Tiger, and whenever I try and use them, they are slow as crap, and, guess what, unstable. Whenever I use Finder to try and access my files, I have to browse through a lot of folders to get to my folder. It can take 5 minutes to get to my folder, not because I have a lot of folders to go trhough, but because I get the pinwheel anytime I get a large list of folders. I mean, WTF? I don't get this issue on the XP computers at my university, nor the Linux machines, only the Apple machines.
My point is that often times, network administrators set things up to work. The key word is work. That doesn't mean it will work well. If they do a poor job of setting the network up and computers up, they will be slow. I didn't use the peformance of my school's computers to judge the performance of how Tiger is in general. I don't think it's fair and if I did that, it wouldn't be giving Apple a fair shot. If I judged my experience with Apple off the experience at my school, I would have to say that Finder simply sucks and Mac OS X Tiger was slow and buggy. So I don't think it's very fair for you to go around saying Vista sucks when the fault may not lie with MS, but rather your network administrators who set the computers up, and this may be attributed to Vista being new and them not being used to it.
If your computer came with Vista, then it probably should be able to run Vista well (there are exceptions with cheapo computers with 512 megs of RAM). I'm sure your network administrators only use driver updates provided by the computer manufacturer, which I often find are severly outdated. I have found that Vista is faster (or just as fast, depending on the app) and more stable than XP on the same computer.