The control layout is essentially the same as all NEX shooters, aside from a few deviations compared to the F3 -- the pop-up flash and its release button are closer to the center, while the playbackbutton is now near the top-center.
Playing YouTube videos on the Q is as easy as tapping an icon on the top of the app with a play button showing some waves coming off, toggling external playback, then playing any video you like.