I got a Nintendo DS, and Mario DS plays extremely well even without an analog stick. They added in a dash button and everything works good.
I don't get all those people saying there isn't enough good games on the DS. There are incredible games already out (Mario, Warioware, PacPix, Star Wars is a great surprise too) and the future games look incredible (Animal Crossing online, Metroid Prime Hunter, Nintendogs, and Miyamoto confirmed a DS exclusive Zelda game).
I love my DS.