From the article:
Remember the solo family doctor? In places like Springfield, it has become increasingly likely that she's collecting a paycheck from a large regional hospital?and practicing medicine according to the hospital's strict playbook. The experience in Springfield is just a needle prick compared with what's going on nationwide. At least one in six doctors?more than 150,000 nationwide?now works as an employee of a hospital system. And with about half of recent medical school graduates deciding to work for hospitals and many established doctors looking to unload their practices amid the tough economic climate, what was a trickle of change has turned into a torrent. Jim Pizzo, a Chicago-area hospital consultant, says the blistering pace of these mergers is leading some colleagues to joke that there are two types of physicians today: "Those employed by hospitals and those about to be."
http://www.smartmoney.com/personal-finance/health-care/farewell-to-the-family-doctor-1298917784955/From reading the article, it appears that the hospitals are imagining a future where they make more money from ACOs because they own the practices. I do wonder what will happen if ACOs fail to materialize. I also wonder how long it will be until the counter-culture starts in earnest.