To be fair, Nintendo isn't supporting the second nub at all. Even Kid Icarus, which has the same awkward and uncomfortable control method as Metroid Prime DS, and isn't out for another three months, doesn't seem to support it.
also, Nintendo announced the last five GBA games. Pretty amazing selection of games.
previously announced: Yoshi's Island (lesser GBA version), Mario Kart, Metroid Fusion, WarioWare, Mario vs Donkey Kong.
newly announced: Wario Land 4, Kirby & Amazing Mirror, Fire Emblem Sacred Stones, Zelda Minish Cap, F-Zero Maximum Velocity.
It has most of the good GBA games on there. Only missing Zero Mission, Warioware Twisted, Advance Wars games, and Drill Dozer, and a few others.