It's still free...well, for my Android phone on the Android Marketplace it's still free. I downloaded it, not even worth the space. It's horrible.
As for it coming to the Xbox, it wouldn't even make it scary then because you could just sit far away from the TV as on the PC you have to be close, unless of course, you have a wireless mouse and wireless keyboard :P The point of the game is to make it seem scary, not play it for fun and not be scared because you're sitting 5 feet away from the TV.
Also, wasn't there a thread almost identical to this? IDK, I may be hallucinating.