Cameron was asked about these tributes in PMQs yesterday. He pledged to have words with Facebook about it. They told him to take a running jump.
Eminent Tellygiraffe commentator Ed West has posted on the matter:
Now, as much as I’ve already expressed my despair at the mongiferous outpourings of sympathy and support for Moat, I do not support any effort to shutdown or otherwise censor, or ban, these sort of pages.
Apparently, Voltaire never actually said “I disagree with what you have to say, but I will defend to the death your right to say it.”
This disappoints me, but the sentiment is no less fundamentally sound for it.