I've noticed that the Wii remotes used in the E3 demos have an extra cord coming in the side. Is that a power source? Will controllers have the option of having a power cord attached (whether it's into the wall or into the GameCube slots)? I think having a power cord would be awesome for single player purposes. I think having wireless controls is only crucial during a multiplayer setting where cords get in the way (or in the case where your batteries die).