For a comparison between the same games on different systems (Wii vs. Gamecube) the Wii does seem to have greatly improved graphics. They compared Madden and Cars on the Wii and the GC. It looks like ...

I've got an XBOX now and a PS2 and of course a PC. There seem to be a lot of games that get simultaneous release on multiple platforms. I generally know that a PC version will have higher resolutions ...