Toy HeadQuarters confirms numerous GBA titles for the year 2001 and hints at Tetris for GameCube.
THQ's release page now has a ton of info on upcoming games across several platforms. They have already confirmed a few GB Advance titles, including Championship Motocross 2002 w/ Ricky Carmichael, Rocket Power (based on a Nickelodeon show), Rugrats, Sponge Bob, and Tetris. There are also a couple of games intriguingly listed for "Next Gen Console" including something called New Legends. It's from developer Infinite Machine, and appears to be a totally new franchise (somebody correct me if I'm wrong). I suggest hitting the link for details. Of course, neither of these games could actually be coming to GameCube, but THQ is friendly enough with the big N to make me think at least the Tetris game will make it to NGC, and probably both of them.