Earlier today, Facebook released version 4.1 of its mobile app for the iPhone, iPod touch, and iPad (App Store link), adding support for Mobile Timeline, among other things. The update also brings improved performance throughout the app, as well as a simplified interface for viewing photos. 

What's New in Version 4.1

  • Access to Mobile Timeline on iPhone (if you already have a timeline). iPad support coming soon. Get your own timeline here: fb.me/tml 
  • Access to friend lists, subscribers and subscriptions
  • Faster, better performance
  • Photos are easier to view, upload and comment on

The update is available for free from the App Store.