TweetDeck has posted a pre-release version of their killer Twitter client that includes Facebook integration:
As the title suggests, v0.24 includes the first elements of Facebook integration into TweetDeck. This integration consists of two elements.
Firstly you can click on the Facebook icon at the top and, once you have signed into Facebook and given TweetDeck authorisation, this will add a new column full of each of your friends most recent status update which updates automatically once a minute. From here you can email the update out to anyone, tweet it out over twitter, view the users online status and if they are online right now click on their name (or the green online status indicator) to open Facebook chat right within TweetDeck.
The other element is the ability to direct your tweet/update to post to twitter or facebook or both directly within the tweet window. Note: direct messages will not be sent via Facebook even if you have the Facebook checkbox ticked.
Nice, especially if you're a TweetDeck user and tired of getting all those inane FB emails that end with "To see the comment thread, follow the link below."