Now I think about the fact that I just looked someone up on contacts.google.com, then added a visit with them to calendar.google.com, and talked with them about it via gmail.com. They know so much about me already, and now they'll have my health history.
The only silver lining is that their security is probably better, and my data is less likely to be hacked and stolen.
But otherwise... Looking forward to a nice Linux/open software fitness watch, from a Kickstarter or other effort, so some of us can take better control of our data.