If MTV does go HDTV for The Real World, this could be a very big step as so far, reality television (whether you love it or hate it) has almost totally been SD-only. The only exception I can think of is American Idol. If The Real World makes the switch, network television will follow. This is not to mention the legions of young people who (like me) have basically grown up with the show and would have an all new reason (like the Xbox 360 and Playstation 3 aren't enough) to buy HDTVs.
Maybe I'm just reading too much into this, but it seems like a great opportunity. They've invested quite a bit in their new station, and this could be a push to get cable and satellite operators to sign up for it. As far as viewers go, no matter what your opinion of reality shows are, it would probably be better in 720p.