I vote for Wii mote and xbox360.
With the Wii mote you just can sit in every pose (I personaly prefer the "sit on the couch with hands on the lean" or the "Stephen Hawking" technique)
The xbox360 gamepad has the buttons on the right place and you don't start sweating when you play hardcore...
And I really DON'T like the PS3 gamepad because it's the opposite of ergonomic design and you sweat like hell. ._.