I really hate to say this, but Anonymous is part of the problem and not part of the solution. Protesting.... ok. But IMO, and INAL, I think it's a bad thing to be hitting any company's computer system. Was it ok to hit SONY? How about any government or any other company? How about your company?
These are treacherous times. Distinguishing between someone doing it for social justice or for monetary gain isn't the way laws work or at least should work. Those of us in IT should understand the dangers and headaches of anyone attacking the systems we're paid to protect.
What the hospital did is so very wrong and they should be held accountable but what this guy did is wrong also. Two wrongs don't make a right.