I guess it depends on what you're looking for. If it's a large concentration of top hospitals with diverse demographics, I would suggest the Boston, MA area. I'm a little biased, I admit, but Boston has great hospitals, and most are affiliated with some top universities and colleges. For example: Mass General, Deaconess, Beth-Israel, Brigham & Women's, Joslin Diabetes Center, Tufts, Boston Medical Center, etc etc etc. Probably the highest concentration of hospitals per capita in the world, LOL.
Boston is a very cool city with lots and lots to do. It does get pretty darned cold, though, and the cost of living can be high.
If money is a motivating factor, a new study shows the Far West and Mid-Atlantic states offer the top average salaries. (New England has been bumped to third place.) I'll include the link: