I don't follow the other systems enough to know what's still coming out for them, but I'm betting PS2 has a lot more life left in it than the GameCube. The system is so popular it's bound to have better support by default. See NES, PSX, and GBA. Anyway, I think joeposh has my number...I'm not so disappointed by the fact that there's one less game next year as I am by the way people use online as an excuse not to put games on the Cube.
Edit: So, in addition to SC: Ghost and Final Fantasy XII, next year PS2 will offer fans Wild Arms 4, Okami, Tales of Legendia, Hitman: Blood Money, Dark Cloud 3, Final Fight: Streetwise, Onimusha: Dawn of Dreams, and...Family Guy!?! Those are some of the highlights, at a glance I'd guess there are about 50 others announced: some will probably be canceled, many will be crappy, but I think that's still a heck of a lot more than GameCube will have next year.