although this thread got really off topic, in large part because of my digression into a rant about haters, i actually found the answer to my original question. I was under the impression that interviews were sent out in waves, meaning they reviewed the whole stack and on a single day sent out all those who were their "first choice" for interviews (as seemed to be the case during med school apps). And it seems some programs do act that way. Mayo for example, sent out a bunch one day and we havent seen anyone post invites from them since. However it appears other programs send out interviews as they review the applications, which appears to be the case for columbia, which had ppl posting invites almost every other day for the past several weeks. so there you have it, for anyone who was interested, some programs send them in waves others stager, i guess its useful to know which does which to gauge whether one has been "screened" out or just not reviewed yet.