I went a little crazy but figure I won't be buying any more games/accessories for a while.
I got:
Mario Strikers Charged
Super Paper Mario
Metroid Prime 3
Warioware Smooth Moves
Elebits
Rayman Raving Rabbids
I already have:
Wii Play
Ice Age 2: The Meltdown
The Godfather: Blackhand Edition
Resident Evil 4 Wii Ed.
I haven't played Warioware or Metroid yet, but all the other games are quite fun. Ice Age 2 is ok, but I mostly bought that because it was cheap and figured my son would get a kick out of it (which he does). I think this is a good mix of single and multiplayer games along with a nice mix of genres. Should keep me entertained for a while.
I used metacritic to help determine which games seemed like good buys.