Cleveland Clinic will start to test the service on at least 1,500 patients. "It will test secure exchange of patient medical record data such as prescriptions, conditions and allergies between their Cleveland Clinic PHR to a secure Google profile in a live clinical delivery setting. The ultimate goal of this patient-centered and controlled model is to give patients the ability to interact with multiple physicians, healthcare service providers and pharmacies. (...) The pilot will eventually extend Cleveland Clinic's online patient services to a broader audience while enabling the portability of patient data so patients can take their data with them wherever they go — even outside the Cleveland Clinic Health System."
The big benefits are that health records become portable, more accessible and more useful, while still being stored securely. Despite the benefits, people might not feel comfortable with storing sensitive data online.
According to New York Times, Google Health will be publicly available after the pilot ends, in around two months.
Update: Google Blog mentions that Google Health uses GData and standard medical information formats. "Patients participating in the Cleveland pilot give authorization via our AuthSub interface to have their electronic medical records safely and securely imported into a Google account. (...) Cleveland is just the first of many healthcare providers that will securely send medical records and information via Google APIs at your request. We've been hard at work collaborating with a number of insurance plans, medical groups, pharmacies and hospitals."