It's Sunday morning and I just wiped out the partition on my trading machine that had Vista on it and am going back to XP.
For the most part, Vista isn't that bad, but there are odd little glitches with certain programs that I just can't explain any other way than a Vista conflict. I was having problems getting some custom written software to work properly (again, unexplained problems, it ran fine on xp machines) and that was the final straw.
If trading is your livelihood, think twice about going into uncharted territory with software, or at least have a backup. Every hang up or problem is potentially lost income.