I dont know if this is known, but I realized you can have youtube playing in the background at all times and in the locked ipod mode also. I am currently running 4.2.1 on a iPhone 4. To do this, play something in the stock youtube app Click home to exit Double click home to get to multitask bar Swipe right to ipod controls Press play and the last thing you had on youtube should play This also works with your playlists! So you can actually hit next and previous from the music controls to go forward and back in your youtube playlist. Seems like this only works from the multitask bar, and not in lock screen. I dont think any other phone is capable of this and its a huge feature for me. I have been making YT playlists of my fave songs for a while, and this will probably slowly take out streaming radio for me. I even have a bunch of playlists for specific school questions, and now I can let them play while driving.