The boxcar app, which is an app that pushes notifications to various twitter apps will be getting an update soon (not sure when) but it is said that it will also support push notifications for facebook 3.0, here is the link
First Look: Boxcar 2.0 – Push Notifications for Twitter, Facebook, and Email | Just Another iPhone Blog
First Look: Boxcar 2.0 – Push Notifications for Twitter, Facebook, and Email | Just Another iPhone Blog