Nintendo needs to make real games on Wii.
For some people's complaints about Nintendo not focusing on "real" games enough, it seems they've got more than they did with GamCube, even before we know what they'll show at E3. For GameCube I think I've got all NOA-released titles for 2001 and 2002. For Wii I've listed titles with dates or that seem pretty sure things for an American release in 2007.
Series showing up on both:
Mario Party 4 - Mario Party 8
Metroid Prime - Metroid Prime 3: Corruption
Super Mario Sunshine - Super Mario Galaxy
Super Smash Bros. Melee - Super Smash Bros. Brawl
GameCube
Animal Crossing
Eternal Darkness: Sanity's Requiem
Luigi's Mansion
Magical Mirror Starring Mickey Mouse
NBA Courtside 2002
Pikmin
Star Fox Adventures
Wave Race: Blue Storm
Wii
Battalion Wars II
Big Brain Academy: Wii Degree
Excite Truck
The Legend of Zelda: Twilight Princess
Mario Strikers Charged
Pokémon Battle Revolution
Super Paper Mario
WarioWare: Smooth Moves
Wii Play
Wii Sports
Bolding those titles that frequently get derided for being nongames, kiddy games, or minigame fests by the hardcore, it leaves an equal amount of "regular games" for both systems.
It's possible a Wii title like Super Mario Galaxy could end up pushed out of 2007, but E3 announcements for games like Fire Emblem should leave the list as long or longer than it appears here.