Nintendo has posted a complete list of GameCube titles, along with videos, screens, and concept art.
Here's the full list:
Luigi's Mansion
Star Fox Adventures: Dinosaur Planet
Super Smash Bros Melee
Pikmin
NBA Courtside 2002
Raven Blade
Wave Race: Blue Storm
Eternal Darkness
Metroid Prime
Kameo: Elements of Power
Donkey Kong Racing
Star Wars Rogue Leader: Rogue Squadron II
Animal Forest
Zelda for Nintendo GameCube
Mario Kart for Nintendo GameCube
Disney's Mickey for Nintendo GameCube
Perfect Dark: Zero
1080 Degree Snowboarding 2
Doshin the Giant
Madden NFL Football
SSX Snowboarder
FIFA Soccer
Resident Evil: Zero
NHL Hitz
NFL Blitz
Monkey Ball
Virtual Striker 3
Phantasy Star Online
Mario Sunshine
Mairionette
100 Mario's
Pokemon
Mario Party 4
Thunder Rally
Too Human
Turok
PGC will work hard to further confirm these titles, as some seem to be coming from nowhere while others are listed differently than the titles we were recently given.