Sermo has grown in the past 12 months from 40,000 to 90,000 licensed physicians.
PatientsLikeMe is seeing their communities evolve in to Disease Management Systems and the evidence they generate may change the discussion on what medications and treatments really work.
These sites are not places where people want to hang out - like on social networking site. What people want is access to relevant information that can help them recover, or manage, their health.
Search is an episodic event. It is hard to build a relationship.
Will doctors trust information from the Internet? The emerging answer seems to be "Yes!" I think this goes back to the upside down view of trust that Clay Shiirky talked about in his keynote session. The Health Care industry seems to think it is important to bring validated information together to enable trust. The real situation is that when people come together and establish trust - then the information flows in a virtuous circle.