this is purely conjecture
but a lot of students who were taken off the wait list last year said that they got an acceptance in june. my guess would be they're just going to send a bunch of acceptances out around then depending on how many people decline acceptances. so, looks like 2 more months of limbo for me
What's the date your letter was postmarked? I'm from Missouri, so I'm wondering if it took longer to get here depending on where you're from. (Long-time lurker, interviewed 3/29, deadline given to me was today)