I wish I could like Vista. I started rolling it out to my clients a couple months after it came out. For the most part, it's ok, but here are my main complaints:
1) it is slow - there are too many instances where the computer should just do something and the screen goes white while that damn circle just keeps rotating. These are times when I'm just navigating folders or going from one folder to another within Outlook. And not all the time, but sometimes - on several computers. Also, it can take so long for folders and their contents to come up. Why the hell does it take 10 seconds to display the control panel? If it was just slow consistently, that would be one thing - but when it's inconsistently slow, that speaks to a flaw in the programming.
2) Display settings don't retain. When a laptop goes to sleep, it will often lose all or part of its display settings on an external monitor. I have several clients with an external display and extended desktops (using the laptop screen). Settings do not remain the same after going to sleep or restarting. This happens with and without docking stations.
3) Believe it or not, I think Vista is more crash prone than XP. I find more illegal program messages in Vista than XP.