So far, according to them, they have given about 175 of about 350 acceptances. Each class is usually comprised of 15 to 20 percent of people that matriculate are from the waitlist for a class of 124 (20-25 from the waitlist).
These are all rough numbers, but probably a good estimate. They didn't really say how many people are initially put on the waitlist though. For some reason though I want to say they said 10% of the waitlist usually is accepted later which would mean 200-250 people on the waitlist (about a third of interviewees).
This really doesn't mean much, but if you like stressing over numbers, there you have it.