Yes, hopefully marxian will find time to update Cutetube for the new API. For me, Cututube is used almost daily so was sad to see it stop working this morning.

As a note, downloading videos still seems to work, so I assume it more or less bypasses the API. Tested with the latest video from Totalbiscuit, http://www.youtube.com/watch?v=RFgFio6FsQg . After download it wouldn't play with the internal player for some reason (temporary maybe), but mplayer did work. So, I guess this might be a viable option until an update arrives.

Edit: Disregard the above, system just needed a long-due reboot, cuteTube works fine again.