Horror Classic Although the recent remake was a fairly enjoyable film in its own right, it is no where near as effective as the original film. I don't think that the similar ties to this and Halloween matter all that much they are different enough and they each build up the atmosphere of dread in their own way.
I think that Black Christmas is the better film, the acting and direction in this film is excellent and the film takes its time to build the sense of danger rather than have the killer hacking his victims from the opening credits. The murders in this film are also more effective than in the remake because you don't see that much, the violence is implied rather than shown and it is far more shocking than anything in the remake.
The fact that you don't know who Billy is or why he is stalking the girls in the house makes him a far more creepy and disturbing killer than those in the films that have followed Black Christmas - the unknown is far more scary than what you see, hence why all the slasher sequels in the 80's and 90's where not really that good when they start to focus more on the killer and less on the victims.
The ending was nice and vague and I'm glad there was never a sequel as it allows you to ponder what happened after the credits rolled. To me the film has aged very well, even if the quality of the picture hasn't whether those who are used to the made slashers and repulsive gore of recent films will like it I don't know, but for me this is a classic well worth seeing.