Rockstar has taken a long-form approach to scaring people with Manhunt 2. They've waited very quietly, very still, until everyone in the UK forgot that it was there, and then they JUMPED OUT AND ANNOUNCED A RELEASE DATE! "BOO! Manhunt 2 is coming out on October 31!"
This version of Manhunt 2 is different from the one the US got, having been "heavily reworked" (as IGN describes it) in a desperate bid for BBFC approval. They got the right to release the game in December, but by then Halloween had already passed, and what's the point of releasing a horror game on any other date?