Big thanks to Mike for sending us a link this social network presentation. It's a holistic view of some of the changes (some identity related) that social networks will be going through over the next few years.
Essentially - you're network and friends are going to come with you, everywhere. Sure, you can change your privacy settings but if you want customized content based on your interests, network and desires you're going to have to give up some of your personal details.
Is this a trade you're willing to make?