Ever used a Roomba? I tell you one thing: every house is going to have a robot vaccuum in the very near future! And everyone is going to want to have a handy receptacle for it. I'd have put my Roomba in a hall closet if any of them had receptacles... It's certainly worth adding a receptacle for in new construction, especially as things like this get more prevalant.
Of course even that might be backwards thing... Right now, there are consumer models for about $250 where the robot vaccuum will literally go off, vaccuum the house and drive back onto its charging platform, but there are a lot of restrictions (namely, that it has to be within line-of-sight of the base) and it can't dump itself out, etc. So, the technology is at a point where you still have to pick the robot up and place it in the charger, and the closet is the prime spot. I'd expect this to change in the coming years, but, unfortunately, homeowners are pretty much stuck with where we put the receptacles now, so it's worth trying to think ahead. That said, I've never heard anyone complain about having too many receptacles