I dual boot myself. It is the best option. For some people they have to use XP for certain things. Like myself. I have been in XP more recently than Vista. Cause of the movie encodes and copying that i am doing i need what XP has to offer. There are more applications that work in XP than Vista for this.
I used Vista for the longest time. I go back to it when i need to. There is almost everything out there that is working on Vista. Just a few apps here and there. But you need a beefy machine to run Vista nicely with all things. Plus you have to have the preference for it. Some people are jsut not into Vista. Same thign for a VMWare version of Vista.