dislikes:
1) resource hog, it shouldn't need that much resources to run - sloppy coding
2) Breaks lots of existing compatible technologies, including network compatibility
3) marketing, I dislike how it was marketed but do kind of like the concept, also there is no need to have like 5 versions of the OS
4) Compare it to other OSes that take up less resources and look just as good if not better with their 3D desktops.
5) Changes - a few changes I like, a lot of them I hate. The security center is no where near intuitive it always takes me several minutes of drilling through it to find the settings to switch all that crap off.
6) Automatic network sharing - that is just lame and I hate how it works automatically
7) The installer takes forever, I mean FOREVER.
8) The cost - 6 years in the making and they want you to pay 200 for an upgrade? not worth it since it doesn't offer any improvements over Xp other than Aero
9) Forced upgrade - I hate how they are trying to force you to upgrade to use certain features that are not in previous OSes mainly DX 10
10) Networking in general is retarded, and I hate how they changed the interface for it. I prefer to browse networks the old way.
11) Broken promises - vista was suppose to have many other features but it didn't at release, which is disappointing.