CBS took issue with his view of Trails and Tribble-ations, claiming it was copyright infringement. In reality, what he does is perfectly legal given the Fair Use Doctrine in copyright law (reviews, parodies and satirical works on copyrighted material are acceptable). However, since YouTube holds to a much stricter interpretation of that law he was left with little wiggle-room.
Since the BBC also took issue with his reviews of Red Dwarf a while back, he decided to remove the reviews from YouTube in order to keep the channel from being permanently shut down.
He now only posts them on his own site and on Blip.tv. The YouTube channel is now only used to put up "previews" of the reviews with a link in the description to Blip.tv.