The YouTube app for both iPhone and iPad has just been updated to version 2.0 and brings with it the ability to watch videos while searching at the same time. You can compare it to looking at a guide on a TV while viewing what's currently playing on TV. The update also supports searching playlists and a play all option to play all the videos in the selected playlist.
To use the picture-in-picture feature of YouTube 2.0, you can tap on the arrow in the upper left hand corner of a video or swipe down on it. The video will move to the bottom right of the screen and allow you to continue to search and navigate through YouTube while the video continues to play. To get rid of the video, just swipe it away to the left.
The play all feature is available for any playlist you have in your account or saved in the app. Underneath the playlist title and description you now have a Play All button that can be tapped to automatically play all the videos in that playlist back to back.
If you notice anything else new, let us know in the comments!