something tells me it was the monies well spent.. .org gives additional credibility to the doctors title ( like they don't care to line their pockets selling you new expensive drugs or something)
It's not really unbelievable just because it's a dot org, since MD is an abbreviation for Doctor of Medicine. The .org TLD would make sense for a medical organization. Don't underestimate .org
That depends on if the name gets attached to a nonprofit organization. MD.org makes great sense for a nonprofit .. would be a shame if they used it to sell Viagra.
As the above stated, it is a great domain, the .org is good for a doctor website and it is 2 letters.