The app will allow for automatic pairing with Google TVs, and manual pairing with your PS3, Xbox, or even just a computer connected to your TV. Once paired, the app will work as a remote control and allow you to control playback of videos, as well as send videos from your iOS device to the big screen.
In addition to the remote control features, the app has also been updated with support for YouTube Capture, which is a separate app that Google created for iOS users to easily... capture video for YouTube. It's all in the name.
If you want to try the YouTube app for iOS, it's available for free in the iTunes App Store.