Tyler loves ours, but he's a bit older (4.5). He loves all the sports games. We haven't even bought any new games yet because he loves those so much.
Mackenzie is 23 mo. We'll take the batteries out of the 2nd remote so she can "play" too. Or she can help me or DH play baseball, bowling, or tennis. She really can't do much by herself. She starts pushing random buttons on the Wii remote and ends up turning it off.
I really want a Wii fit!