According to this 1UP story and plenty of other reports, Bethesda sent out a general notice last night asking that “all Fallout 3 trailers” be removed from sites.
God knows what’s happened here, but footage has been in the hands of the media for months. It’s apparently been withdrawn at the request of the ESRB and seems to be limited to US sites.
May as well get in one final bit of censorship before the game launches, eh? It reviewed quite well, so Bethesda’s probably stoical about the whole thing.
Full story through the link.