Ok here we go.
1. Vista Aero - This looks awesome. You can view your desktop in full 3D. The only downfall is the basic version doesnt have it.
2. It is much safer
3. More user friendly
Cons
1.You need a pretty good system to use Vista.
2.Aero requires a good video card.
2. New GUI. It looks pretty. Flip 3D is really cool:
Live thumbnails:
3. The search doesn't take like 9 hours like it does in XP.
4. Better security?
5. Networking is easy to setup. Haven't actually used it, but so I hear.
I did notice that it wasn't quite as snappy as XP is, but it's only the prerelease RTM version that I was using, so I figure by the time of the official release, they'll have that fixed.