Well, I had lots more Visual Studio crashes. I even got it down to the point where I could crash it on every build. I decided to uninstall Ankh, which was sad because it's a cool tool (Visual Studio integration for SubVersion). I don't think that's the real root cause, but it does appear that the root cause ricocheted a bullet into Ankh's head that brought VS down. I think the real cause is something horked up in our project somewhere (Bryan is getting some weirdness, too and he is running Server 2008 and VS without SP1).
So, all this to say, I retract blame from Vista SP1. In fact, I was pretty pleased at how smooth the install process was and how it managed its own multiple reboots for multiple updates and such.