Even though few people can clearly define Web 2.0, many of its emerging components such as blogs, wikis, video-sharing – social networking activities -- have made millionaires of a whole new breed of geeky entrepreneur. Google paid more than $1.6bn for YouTube. By some accounts FaceBook is valued at over $600 million. And the $580 million News Corp. paid for MySpace looks like a bargain.

Does the social networking trend matter in healthcare? Several new companies are betting the answer is "yes."

The most prominent of these is Revolution Health, the company backed by AOL founder Steve Case. It launched its website in late December, and already has blogs, community message boards, consumer health information, and a host of tools on offer. You can even read Case's blog.

Revolution is by no means alone. Organized Wisdom launched its core site in October 2006. It started providing access to content from HealthWise, and the ability for consumers to create "WisdomCards"— information about how they handled particular health issues. Around the same time, DailyStrength.org appeared. It hosts communities around particular diseases, and allows people to connect, message and share experiences within 600 online communities. DailyStrength's CEO Doug Hirsch says communities discussing depression, bereavement, divorce, cystic fibrosis, and autism are among the most popular.

Other similar sites include Patients Like Me, a community currently focused on ALS.

While email list-serves for patients have been around for a decade-plus, Hirsch (who used to run Yahoo Groups) believes patients and caregivers like tools that help them support each other. Coming next are tools that help them set goals, rate providers, and diagnose problems. OrganizedWisdom President & COO Unity Stoakes says his site will add messaging and tools "to build around the wisdom." The idea is the collective experience will help others far into the future.

Healthcare social networking generally is experiencing steep traffic growth, much of it based on search engines or user referrals. OrganizedWisdom claims over 1.3 million visits last month, in part from re-routing traffic from 35 condition-specific sites. DailyStrength claims over 120,000 unique visitors with 20,000 registered users. Remember that both these sites are less than four months old. Both are planning to monetize their communities by taking clearly delineated advertising and sponsorship.

Another new social networking site called Sermo, which allows only physicians to register, is showing even faster growth. It has already 6,000 registered users, and CEO Daniel Palestrand says more than 400 are joining each week. Sermo allows physicians to ask and answer questions and share opinions on a wide range of medical issues, and rank each other's answers. Sermo aggregates that data and sells it to financial companies, government agencies, and eventually (but not yet) pharmaceutical companies.

The model is convincing enough that last week Sermo raised a second round of funding of $9.5m, while both OrganizedWisdom and DailyStrength already have raised smaller amounts. It seems that venture capitalists, at least, think social networking in healthcare is well on its way.

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