I wouldn't worry about having not heard anything yet- from what I can tell, it's impossible to guess what any of the schools are actually doing- I've heard that some schools will interview, but some years they've offered spots without interviews.
I feel like it has a lot to do with the department heads at each school. If they like your writing, your cv, your personal statement, if something in any of those documents rings true to them, that is what really matters. I don't have a ton of production history (a few one-act productions, and a handful of readings) but I feel like everything else (theatre work history, publication in non-playwriting genres, diverse education history -ie non-trad and not Ivy League) plays a BIG part in getting the attention of the selection committee or the department head.
Honesty, hard-work and a positive attitude are the secret... God, I sound like my Grandpa.
-R