The New York Times has a piece today that features the Zuri, Healthvault, and Google Health:
Keeping Your Own Health Chart, Online
The article discusses a number of uses for this kind of combined (medical device plus PHR) functionality. Besides the obvious, it's interesting that clinical trial matching (TrialX) is also mentioned.
User control of on-line health information has many hurdles to overcome. Even with adequate security:
First, however, patients will have to become comfortable placing medical data like readings from home tests online.