I just wanted to give big GOOD LUCK to all R2 applicants!
I know first hand how nervous you are/were to hit that submit button, and how hard it is now to go into the waiting phase. Some will say you should relax, because (other than your interview) it is all out of your hands now. For me, and I'm sure most applicants, that is exactly why it's so hard!! If you had some control you could at least DO something!
I'd say you should take this opportunity to catch up on some good TV. But if you live in the US, there isn't much to look forward to with the writers strike going on. Of course, during this one period in the next several years when we'll actually have time to watch TV and there is nothing on, right?! Except, of course, American Idol (blah) and a little bit of Lost (yay!).
In all seriousness though, the only thing that got me through the waiting game with some sanity was to keep myself distracted with other projects. I recommend you try to do the same :)