Basically, everything on the web-version of Facebook has been condensed down into a slick application for the iPhone and iPod Touch.
My problem with the Facebook application before, was that it didn't have a status update feature and lacked a few others: new home page, comments, ability to read notes, ability to see posted items, etc...
Check out a photo below from TechCrunch:
This update alleviates all of my past issues with the Facebook App in the past. The update is well worth downloading.
You can download the updated version here.