I think I'll love Mario Kart DS when I get it in a few days. However, I REALLY l,ove Daigasso! Band Brothers (I think it's my favorite), Super Mario 64 DS, and Tennis no Ojii-sama 2005 Crystal Drive (Prince of Tennis). I heard Phoenix Wright is good, but I'm also getting that in a few days, so we'll see.
Ouendan and Jump! Superstars is fun, but not as fun as those mentioned above.