Vista for me has been nothing short of perfection
I never was a fan of MAC OS or Linux.
No malware attacks, Better built in security. UAC is annoying, but it works. To me, thats all that matters.
Only a few crashes resulting from some slightly outdated software.
Better default GUI. Don't need to install so much crapware to better the interface. In fact, I still use AERO, don't have any GUI enhancement software, or extra skins installed. Personally, I think AERO is a greater GUI than Luna or any other XP skin will ever be.
Slightly slower boot time, but nothing I'm going to throw a hissy fit over.
Less time spent downloading patches/upgrades from WU.
Windows (Live) Photo Gallery. Something XP should have had. I love using this app for my pics.
Games Explorer (Love it)
The built in games have been redone to include better graphics as compared to XP.
Two system restores.
Malware attacks (Even with AV).
Crapware driveby installs.
Kind of a cruddy GUI. Sorry, I never did like Luna. Although, I wish M$ had used Luna Element 5.1, that skin was sexy! Haha.
Spent to much time trying to figure out problems.
Kinda felt like something was missing. Still had outdated apps installed. Using Paint, solitaire, minesweeper, etc. made me feel like it was 1995 again, lo-res icons, same old windows.... long story short, It was an old OS with a new paint job. XP could have been better if M$ really gave all its energy to it. I hate it when parts of the OS is neglected over time and your left with this rather odd feeling of is this worth my money?
Just all around I think Vista is the better OS. Its new, fresh, re-done from the ground up, it has that new OS smell to it. Sure it has its quirks, but nothing XP hasn't gone through at one point in its life. You just need to make sure you have acceptable hardware (Dual/Quad core processor, 2GB or greater RAM, DX10 card, etc...), or yes, your Vista experience will suck. Mine sucked until I upgraded my hardware. =/