Dude, just buy it now. The single player is excellent, and the multiplayer has some serious legs.
Particularly the Courtesan MP model. She slices your throat open. With a FAN.
I like the Doctor, personally. Always had a thing for plague doctors, thought they were awesome since we first learned about them in 10th grade.
I usually play the Prowler, or failing that the Officer. The bit about the Courtesan was just for pun.
I would suggest getting it now if you want to try the multiplayer. It isn’t Call of Duty, Halo, etc. so who knows how long people will actually be playing it?
And I don’t have a preference in the MP character department yet. Though the Courtesan is easy on the eyes.
/wishes he had xbox live 
If I had a 48 hour code I’d give it to you, but it seems like they stopped giving them out like candy
(unless you mean it’s impossible for you to connect your 360)
DO EET!
Deadly Harlequin pre-order character is my personal favorite. I think its the mask. Fucking clowns, it never ends with them. Of course its also just as fun to kill one of them.
Engineer here, dat beard.
can’t believe my brother got the game for 360, we don’t even have Live. Hope the SP campaign is worth the full retail price 
Assassin’s Creed is all about the SP campaign, you should be worried about the multiplayer, even though it is really awesome.
Assbro
What Dethklok said. The series really is about the story, and the multiplayer actually being good is a nice bonus.
When I first heard they were adding multiplayer my heart sank because I was afraid it was just going to be some generic crap, but not only did they come up with something awesome, they actually made it work with the story. I was very, very happy when it turned out to be awesome instead of crap.