well, one thing you could do is check the respective school in question's website. harvard explicitly says it somewhere on their's. also, you could do what i just did, but apparently didn't before (silly me) and look in the msar. in that little box packed with information, one of the items is:
Acceptance notice to regular applicants
Earliest date:
Latest date:
It seems like the non-rolling ones have a much later earliest date than most schools. i.e. most i've seen are October 15 or so. Duke is Feb 28. Something odd, though. Harvard's earliest and latest dates are both Feb 28. So do they then presume to know exactly the number of acceptances it will take to fill the class? I mean, not a lot of people are going to turn down Hahvard, but there are a few insane(ly intelligent) ones that do, Like Jessica on SD/\/ from last app cycle. Dude, she rocked!
So, how do Texans do a snooty accent, like pronounce Hahvard. hmmmm, something to think about...