Google: Health Records?

Google will begin storing the medical records of a few thousand patients from the Cleveland Clinic who volunteered for an electronic transfer of their personal health records so they can be retrieved through Google's new service. The advantage is the easy access to their own medical records and the simplifying of transferring medical records when changing doctors. The dangers are however great, placing your most personal information on the net is an invitation to hacker's. If I were approached with the opportunity to take part in this trial, I would respectfully decline because I do not completely trust the security of the internet just yet. Also, since Google is in the business of making profits like any other firm, I am curious to know how they plan on making this profitable for themselves. I mean are they just doing us a service?