Pakistan, Afghanistan and several other nations have announced that they are blocking YouTube in whole or in part in an effort to prevent people from viewing the 14-minute trailer of the film Innocence of Muslims.
The trailer has caused widespread protests around the Muslim world, purporting to show a movie, so far unseen, which mocks the Prophet Muhammed. There has been speculation that the movie itself doesn’t even exist, and that all that was ever made was the trailer itself.
Google seems to be getting in on the blocking of the trailer as well, though they maintain that it doesn’t violate the terms of service for YouTube and won’t be removed outright. So far they have blocked access to the trailer for Libyans and Egyptians.
YouTube is one of several sites which has regularly been blocked in more authoritarian nations to prevent its use by dissidents. It has also regularly been banned, though usually briefly, by countries accusing it of hosting blasphemous content.