vq=... is a trick, normally youtube automatically chooses for you a quality depends on your bandwidth and size of the embedded window. It is possible that it does not work in all environments but try this:
Code:
http://www.youtube.com/v/{serviceVAL}?version=3&autoplay={ap10}&vq=hd720&fs=1
or
Code:
http://www.youtube.com/v/{serviceVAL}?version=3&autoplay={ap10}&vq=hd1080&fs=1