Disney has released some screens of their DGamer service, a social network integrated with the company's upcoming DS games that allows avatar creation and chat. There's a lot to like about the service, in general: it provides a platform-wide (or, at least, common to Disney's games) interface for connecting with online friends, and avatars and accounts are usable on both PC and DS. Chat is moderated by Disney employees on the lookout for potential security problems. It also includes "Honors" for each supported game, which are similar to Xbox Live's Achievements. You'll be able to see how much time someone has put into Prince Caspian, and then ask them why they're playing so much Prince Caspian! That's the first game to support DGamer, but Spectrobes: Beyond the Portals will as well.
The downside is that you have to represent yourself as something like the avatar pictured. Do you want to connect with your friends if that's how you'll be doing it? Maybe it's a security feature -- kids won't want to talk to strangers looking like that. Oh, and also it's got its own version of friend codes.