There was an announcement made this week about Visual Studio 2005 SP1 and support for Vista. In a nutshell, SP1 won't resolve all the issues of running VS on Vista. However, I want to point out that if you're developing Windows Mobile applications, there isn't much to worry about. I've been using Visual Studio on Vista for months now, developing and debugging both managed and native applications. Apart from a few setup issues, everything works great. The minor setup issues have workarounds that were mentioned on the VSD blog a while back. I've been told by the VSD team that these issues will be also fixed in SP1 instead of the post-Vista update, so that's great news.
I've recorded this short 8 minute video that demos running Visual Studio on Vista. Hope this helps you decide whether to take the plunge and start using Vista if you're not already beta testing it. Click here to watch video.