Do I need to wait till after May 15th to figure out what is going on, or will there be movement before that? Thanks for your input
It doesn't hurt to figure out how waitlists work for various schools. It might help if you do get acceptances to other schools but still have interest in the schools that waitlisted you.
Waitlists really depends on the schools. For most schools you don't see significant movement until after may 15th. Many of the schools I applied to did not rank waitlists until after that. Some will give you a hard position (you are number x out of x people, we normally pull off the waitlist to place x, on average), some break you into tiers(high, middle, low priority where they normally take all high priority), and some don't tell you anything. All of this really depends on how many people end up declining acceptances by May 15th. For example, my school overaccepted last year and not enough people declined acceptances, so the school took almost no one(if anyone) off the waitlist and actually had 50 people too many in the class. Before that year they did go into the waitlist, It happens, you never now what is going to occur but can guess based on the past.
Some schools pull heavily off the waitlist. I know traditionally some "mid-tier" schools might take half a class off the waitlist. Some schools take 1-10 people, at max.
You can, which I advise you to do both:
a. call the school and ask about average amount of people taken off the waitlist and how ranking is done.
b. look up the 2010-2011 and 2009-2010 class threads for the schools you want to know about and see how waitlist movement has occurred in the past.