"What if they had a wireless multitap 'wave-tap' that you plug conrollers into and the multi-tap just pretends each contoller is a wave-bird, and communicates with the system.
The system sounds way too small to have 4 contoller ports anywhere on it, I like this idea alot better."
Sigh ... the Revolution controllers will be backwards compatible as well. You'll use them to play GameCube games. No controller ports are necessary.
As for the memory cards, they might keep the same format, and just move up to larger sizes (like the PS2 did), or they might go with a completely new format, or you'll store them on internal storage. So you might have to start your games over (unless you have a USB card reader), but the games themselves will be compatible, as promised.
Wait, did I say something about internal storage? Scratch that.