On line health records are probably a good idea and offer a number of advantages over off line decentralized health records. In the event that there is an emergency and it ia needed,having health records in on easily located place makes it easier for health care workers to access a permanent version of your health history. No longer will you records be placed in a hospitals archives where they are not easily gotten.
When I recently went to NYU emergency room and I was passing a kidney stone, I still had to give the doctors and the triage nurse, my medical history, even though I have been using that facility exclusively for over 30 years. With online records, my history would be instantly found by anyone I gave permission to access them.
Although these online records are a good idea, to my knowledge, congress has not passed adequate laws concerning third party protection of these records from abuse, such as data mining and other invasions of privacy. This month Google has launched Google Health, their attempt at the development of centralized Internet accessible health records. I am both excited and concerned about what Google does with this new project.