Awhile back, we covered an issue regarding Vista migration, and it's come up again. Computerworld just posted an article outlining why it makes a lot of sense to upgrade to Mac OS in the coming year rather than Vista.
In a nutshell, the article argues that if you're going to put up with the time, expense and effort to move to what is likely to be a very iffy platform for at least the next year, then why not simply move to a more stable system that has a proven track record of reliability, systems compatibility and superior functionality?
A Mac will still be able to integrate with a Windows-based infrastructure, and with an IntelMac, you can even virtualize a Vista or XP environment should you need to interface directly with either of those systems.
Certainly could be worth investigating.