HD Penetration.

[johnsobas]

I think the percentage using it to play video games is small.  I would be interested to see the numbers though, i bet most ps3 owners have HDTV, but 360 is probably less than 50%. 

Honestly i think that many HDTV owners don't even use the HD on it.  Not only that but even if a household has a HDTV, and the same household has a PS3 or 360 it doesn't mean that they usually use the PS3 on that TV.  Many people want to game on the smaller TVs in their own rooms rather than the big TV in the main room (common scenario).