I think WL movement will be very different this year because the AAMC has decreased the amount of information given to schools. In the past(last year), they were able to see all the schools every applicant who applied to their school applied to and every status of the applicant(if they were given a secondary, interview, acceptance, waitlist etc.). Currently, they can see how many schools you applied to and how many schools you've been interviewed, accepted, waitlisted etc. but with no names of the other schools. Before they would use the information about the other schools to gauge if you were likely to come to their school or not but now they can't so I think they are being conservative with their acceptances. That's why now they have the self-report for UF when you are accepted to gauge your level of interest. That being said all schools are in that same boat so my guess is when people finally commit to enroll wherever there will be more movement than expected. Just my two cents.
**My source for this information comes from 3 interviews I've been on where they all said the same thing where they have decreased info this year.