First, congrats to all the 2014 acceptances! Hope to see you all at Second Look!
I'm a student interviewer on the admissions committee now, and I just wanted to make a few comments. I remember, way back when, checking the Duke thread religiously, and being ridiculously stressed out about every little detail of the admissions process up until I finally got that fat yellow envelope, then sympathizing with other SDN'ers (and now current classmates!) who got ridiculously stressed out about the waitlist. So hopefully I can say a few things to alleviate some anxiety, or at least clear up some misconceptions.
As someone else noted, there were about 1200 interviews (including MSTP) this year. I think the DukeMed Alumni News article took data from previous years, which is why the quoted 750 interviews there is a little lower than this year's numbers.
As with most other medical schools, Duke does initially accept more students than there are slots, knowing that people will, for whatever reason, decline to attend. I don't know that I can give specific numbers on admissions/wait list for this year's admissions cycle, but I would say that the percentage of interviewees accepted this year is about the same as it has been in previous years (see article above).
In determining who to accept/waitlist/reject, I would absolutely refute whoever made the claim that Duke is just a "stat *****". (Trust me, I do have classmates who had abysmal grades or MCAT scores < 30, but are just really awesome people.) It's true that Duke does heavily emphasize grades and MCAT scores, but that's probably because, like most other top med schools, they can afford to. However, more than that, I've always felt that Duke truly does want to find students who can be outstanding academically, while also being capable of outstanding humanism, and I feel even more sure of that after having served on the admissions committee. Everyone I interviewed who got in was outstanding and definitely deserved an admit. On the flip side, I interviewed some excellent candidates who I thought would be accepted, but they were waitlisted for things like less-than-stellar grades or MCATs. My point is, it's a really competitive field, and we get so many more qualified applicants than we have available slots.
As for the wait list, it is extremely variable from year to year. I think my class pulled ~10 off the waitlist, whereas the class above mine had ~30. If you're on the wait list and still truly interested in Duke, I don't think it hurts to send an update letter proclaiming your continued love and affection. As far as I know, the wait list is not ranked. However, I have heard that the admissions committee tries to make a "balanced" class, so that if an admit declines, they try to pull someone off the waitlist with similar qualities. For example, if someone who declines happens to be a Midwesterner from a small liberal arts college who majored in particle physics and likes global health, the admissions committee will likely pull another Midwestern particle physicist who likes global health off the waitlist. Of course, that's all hearsay, but either way the committee works really hard to craft a dynamic class that gets along with each other pretty well.
Lastly, to offer some hope for those still waiting to hear, I think there are actually a few decisions yet to be made. Not sure of the specifics there, but nothing is set in stone!
That's all I've got to say for now. Best wishes for everyone who's been following Duke!