Odds of Getting In
Because of the continual advancements in the field of science and medicine, and because people will reliably continue to get sick or injured on a regular basis, the medical profession isn't going to be out of vogue any time soon. Your chances are very good if you're willing to take more or less any specialty.
Want to be a brain surgeon? Good luck. It's a very competitive area that the best and brightest fight for. Hard.
Want to have a nice life and make real dough without the stress of surgery? Go into dermatology—the profession restricts the number of new docs admitted each year so that there are never "really enough" zit poppers. So prices stay high and the field is a great balance of life quality and dough.
Regardless, it's a fight. You gotta want it. Or do something else.