If you haven't used Friends, it lets you check you feeds on Facebook, Twitter, MySpace, and LinkedIn. You can sync your contacts from those services (and others) with your device's address book, mark contacts as favorites for easy access, and post to multiple services at once.
The updated app has a redesigned user interface that offers an at-a-glance overview of your Facebook and Twitter feeds on the home page, as well as faster access to filtering for a specific service and its contacts. You can now save links to your Read It Later account (in addition to existing support for Instapaper), and syncing your phone's contacts with LinkedIn has been improved. Users can also now sort their contacts by first and last names, instead of last name alone. A number of bugs were fixed for this update, too.
Friends is on sale right now for just $1 (down from its usual $2 price), and is compatible with devices running iOS 4.0 or later.