I just rebuilt a new ROM with updated gecko and gaia. Video is quite good, thumbnailing somehow works, yet there are still crashes with video, sometimes (if you stop it without pausing for example).
Stuff for fastboot flashing available at https://docs.google.com/file/d/0B1U1Qmjcn5OOalZHZl9Jel9OR2M/edit
Stuff for fastboot flashing available at https://docs.google.com/file/d/0B1U1Qmjcn5OOalZHZl9Jel9OR2M/edit