Most schools usually accept more than there set amount. Several usually drop due to either multiple acceptances or various other reasons that occur relatively quickly. Generally schools go from an unranked waitlist to a ranked waitlist in June/July and as people drop due to not meeting the set requirements by the date indicated, family reasons, financial reasons, change of heart, etc. The schools then just take the person from the top of the list. These drops often occur right up till the actual start of classes so don't give up hope! Unfortunately, it is a long and tedious wait and unless you are lucky early on it may continue. A lot of schools will let you know what number you are on the waitlist though after they have done the rankings and let you know, but some schools prefer to keep it to themselves. Call and ask it can't hurt you!