Atomkeep is a service that lets you sync, import, and merge your personal profile data across multiple services. It's trying to solve one of the many side effects of service saturation by giving people a central place to manage personal data on a pretty grand scale, like say every popular service you're using right now.
Changed your address? Don't bother logging in to each place to make the change. Instead you can edit your AtomKeep profile (which contains nearly every conceivable field) and then push it out to just the services you want, or all of them at once. You can also bring in your profile data from any service you're signed up for, and merge it in to your Atomkeep profile to push back out to other places. It's actually incredibly simple to manage.
One thing to note is that Atomkeep doesn't hang on to any of your passwords. It's nice enough to keep your username for each service, but that doesn't make having to re-enter your password across four or five of the 23 available services any easier. Ideally, future iterations could adopt a system similar to Roboform or Passpack, with a master password that supersedes your account password to unlock a treasure trove of log-ins. As the service scales to integrate more and more sites, this is going to be the one thing holding it back from being truly user friendly.
In addition to its core profile service, you can also take all your social profiles and stick them on a badge that can be dropped into blogs or e-mails. Other users can then click on any service icon and be taken straight to that profile as long as it's public. There's even an option to drop in your resume, which can be pulled in from services like Facebook simply using your work history, or a fully formatted version from places like Monster and LinkedIn.