Andrey Doronichev on the official YouTube blog:
For all you diehard YouTube fans out there who can’t get enough YouTube on your mobile, we’ve got some great news: starting today, you can download the official YouTube app for iPhone and iPod touch from the App Store, bringing you more of the videos you love and more ways to share them with the people you care about.
The new app features access to more videos, a new channel guide, predictive search suggestions, sharing on Google+, Facebook and text message and more. It’s a free download.
This is a replacement for the “built-in” app included with iOS 5, which will go away with the next major iOS release.
No background audio. Shame
Other than the background audio missing, this is a HUGE improvement over the (virtually useless) built-in app.
An improvement if you only view on your phone, but it’s missing a key feature for me. My primary use for YouTube on my iPhone is to select videos to play on my Apple TV. This YouTube app requires me to use mirroring to play video rather than streaming it directly, which means the video doesn’t play full screen. So I’ve got an extra step and lower quality. Terrible.
You forgot to include “advertisements” in your list of new features.