Well the application process is pretty simple--just fill out their application and submit 2-3 letters of rec along with your SAT or GRE scores. I'm a current student (anxious about the fall....) and I went through the process last year. I can't really give you stats on my classmates (as I feel like a douche asking them how their GRE or SAT scores were or what was their GPA); but from the directory, it definitely seems like a sizable amount of students have attended top 25 undergrad institutions.
Anyway, you can always give Sara a call (she's the admin, DeEttra, the director is really busy, and Sara does look through the files of potential applicants and has a very good sense of the stats of such applicants) and she could give you more info on the average GPA (I think it's a 3.6 cgpa). I think this year she anticipates the first interviews to be given around October/November (Application will open September 1).
In general, try to get your application in by October. Last year they interviewed a bit late--November being the first 2-3 people interviewed, then late January as the second batch.
Another thing, while it seems to me numbers may be important, I really think that the staff here evaluate all applicants holistically. I had pretty good but not amazing SAT scores (2140/2400) and not a very good GPA at all (3.4 undergrad), but was pretty much accepted the day I was interviewed. That being said, even if one's GPA is as low as mine, just know that your work is really cut out for you once the program starts (I'm going to need pretty much all A's to even have a shot at CA schools/MD schools in general; and a killer MCAT). I'm probably an outlier...now that I think about it.
