The short of it: Seesmic Desktop now lets you use Facebook on the desktop in the same way that it - and rival TweetDeck - allowed you to use Twitter. But while TweetDeck was the first to let you post updates to Facebook, the Facebook API is enabling you to receive all your Facebook updates on the desktop, and even "like" these feed items without ever visiting Facebook.com.
I've been testing the new version of the app this afternoon and it's mightily impressive, pulling in thumbnails and letting you break off certain users into new userlist columns. The drawback, however, is that most of my friends simply use their Facebook feed to repost their Twitter messages.
We covered the features of this new release earlier this week, but today it should become widely available. Also check out the video below for information on the new release.