Joe,
We'll have to test this, as it isn't something we've ever run into. Can you test this on our JFBConnect demo site and see if you run into the same problem?
www.sourcecoast.com/jfbconnect/demo/
The only time we import profile information into JomSocial is during logging in or registration. So, there's no reason we should be blocking an update of profile information while the user is actively on the site. I could easily see how we'd overwrite that data on a return visit, if you have JFBConnect configured that way.
Thanks, and let us know if you find anything out!
Alex