Like that's the whole point, yeah? I ask because I have my TV, 360, Wii, PS2, Genesis, and SNES all connected to the same power strip. Only two are ever on at the same time though, except the PS2 and Wii are always in sleep mode. I'm totally cool and have no need to worry about fires burning down my house?
You should be fine. I've had my 360, Wii, and PS3 plugged into the same power strip for years along with my TV, DVR, and sound system, and I've never had any problems.
~15-20 watts for a Wii in game mode, not sure on older systems. 360 draw < 100 watts in game mode, I'm not entirely sure how much energy they draw in standby or when the are off, but as long as they are plugged into something they do draw energy.