They actually did not give us numbers updates that I remember. But a little bird on SDN told me that as of Monday (just before the last burst of acceptances on here) there were 26 slots in the class.
As far as the actual interviews go for people who were asking about that: It's pretty standard. I got a lot of clarifying questions about my application, a little "Why Mayo?", and a question about whether I can really see myself living in Rochester for 4 years. Be ready for that last one, because I am still a little unsure and that may have come across. Also f you haven't figured this out already, Mayo is all about the patients, so if you don't mention patients at all in your interview then you are probably losing the game.
Anyway, Mayo is a gorgeous place with a phenomenal number of opportunities. Now to wait for about a month...