I dealt with Case last year. I interviewed with them in October (off site, at Henry Ford Hospital). I was put in the hold category shortly after. Later I was put on the wait list. However, I do remember people that were put in the hold category and then rejected. Finally in late June I was offered a spot off of the wait list.
Dylann FMD's response seems to be how I remember it. However, I would not go around thinking that schools do not pull people off of the hold and waitlist categories. Last year I started interviewing in September and did fourteen interviews, all at schools in the USnews top thirty. I was put in the hold category, waitlist category, or rejected by all fourteen. I did not get my first acceptance until May 15th. Remember that date! it's very real! From then until the first week of July I received four additional acceptances.
In the spring I started to send schools short letters addressed to the dean saying that I was still interested and asked them to keep my file under consideration (I know that I sent Case at least one letter like this). In the spring I also chose my first choice school and sent them a letter saying basically the same thing but I also said that it was my first choice and that I would definetely accept a spot if offered and that I would withdraw from all other schools (I ended up getting into my first choice school in July).
One last point: Don't send the "you're my first choice" letter to more than one school. I was told my the admissions committee at one interview that they can communicate with other schools and that if they found out you did this with another school they would take back their offer of acceptance.
Good luck with applying. Don't get discouraged if May rolls around and you only have a bunch of waitlists. It worked out for me, many of my classmates, and many of my friends at schools all over the country.
If any one has any questions feel free to email me. I really only check this site when I'm not in school.