That would be a pretty good thing in my opinion. Cross platform play maybe? Ability to play games on both platforms by buying one copy? Possibilities are endless. Screenshots function? Yes please!
Actually read the comments.
Is this a joke? people are just noticing this? That's been there for like, 1 or 2 years. It's for contacting VALVe if you have problems with any of there games on Xbox.
Heck, there's even a dedicated Xbox sub-forum on the Steam Forums!
(about 3/4 the way down)