I think it will become more common to see power outlets with four plugs in them. Our power needs are frequently served by power boards to provide multiple outlets, and it only makes sense that these would start to be incorporated into the design of newer houses. Perhaps at first it would just be areas like the kitchen and lounge room where the most devices are plugged in, but I see no reason not to extend the same allowances to bedrooms and other places too.
Mokalus of Borg
PS - I'd like to have a few four-plug outlets installed at home.
PPS - And battery backup built-in would be nice, too.