Bit of a late post but that's something I actually only looked into myself. The oculus I already knew about but that running thing is pretty cool too.
That being said, I would probably have to get in shape just to be able to use that for my hours-long gaming sessions. Which is not so much a con (need to get in shape anyway), but is still a point to make.
Edit: I'd probably be fine without the simulated hits by bullets and such, though it still sounds pretty awesome.