DO’s: The "fake Rolex" of the medical profession?

Paris Hilton’s psychiatrist is apparently a Doctor of Osteopathy, and the press doesn’t quite understand what the degree means:

Sophy is actually a D.O., or Doctor of Osteopathy. Though osteopaths are still considered licensed doctors in America (not, however, in Europe) and Sophy serves as the legitimate medical director of the L.A. County Department of Family and Child Services, he does not seem eager to tout his full credentials””perhaps because a D.O. is considered by many M.D.s to be the fake Rolex of the medical profession.