i think kaplan, the princeton review, and exam krackers happened to the 30. i've heard estimates that the number of med school applicants who take test prep classes of some kind is over 50%. although the mcat is more of a test of knowledge than the sat (which, for a large part, tests your ability to take the sat,) this principle still applies. in a few years, the 28s and 29s of the world may be mostly reserved for d.o. schools and foreign m.d. programs.
of course, i wouldn't be surprised if somehow the test was altered to adjust the mean and median scores. and we also don't know what the computerized version of the exam will do for the next batch of scores.