VLC media player was just updated as a universal app for iPhone and iPad in the App Store. The popular, open source, cross platform media player has been a favorite on Windows, OS X and Linux for years.
Awhile back, VLC released an iPad app in the App Store, and surprisingly the app was approved. VLC for iPhone allows you to play nearly every kind of video format known to man. The app clearly duplicates (and in my opinion, makes better) the video playback functionality of the the native iPod app. So, it's interesting that Apple has finally approved it.
The developers of the VideoLAN player just got the VLC 1.1.0 update approved, which lets VLC run on the iPhone 4, iPhone 3GS, and recent iPod touch models. I downloaded the app, and I was impressed.