Facebook has several layers of functionality that make it worth using, but my favorite is the once-controversial news feed. Why? I simply don't have time to check each of my friend's profiles for what's new, and the feed does a pretty great job at that without all the legwork or annoying e-mail notifications. FriendFeed is a new service that takes the idea of a news feed and extends it beyond the social network into other social services you're a part of. There are more than 20 to pick and choose from, including social news services like Digg, Delicious, and Reddit, along with microblogs like Twitter, Jaiku and Pownce.
By adding all these services to your FriendFeed, you're essentially creating another social networking profile--but this is a little different. It's almost like a digital identity, or your very own "about" page of services you use. Others can then easily subscribe to your FriendFeed and get the benefit of all of your online activity in one place. Likewise you can subscribe to theirs with one click, and track all the online activity they've made publicly available.
So what's the big deal about this service? It's really not a new idea--other services like Readr, Spokeo, Jaiku (which is incidentally one of the included feeds) let you do this with all sorts of social feeds, and 8hands, which we looked at back in late April, does it on your desktop with IM to boot. There's also the recently launched Plaxo Pulse (review), which adds some contact management into the mix as well. So to answer my original question, the most exciting part is the group of folks behind it, which consists of four ex-Google employees who have worked on big projects like Google Maps, Groups, and Gmail. That and it's super simple to use--you just need to copy and paste a few URLs, and plug in your username.
The service is in private beta with plans to open up to everyone in the "next month or so."