I love Assassins Creeds.. I own them all and I believe they are some of the best games you can have. Before reading this review.. please understand that I have not got XBOX live at the moment, so I have only played this on single player.. so this review is solely on the campaign..
The game itself is great, just like the previous games.. you can go anywhere and do almost anything.. they have also imported from AC2.. the ability to invest in a city.. which I personally loved.
With regards to the missions, I believe they are slightly better than the previous games.. less chasing after people and more stealth.. A LOT MORE STEALTH.. which is an interesting improvement.
The biggest change of course is the brotherhood.. I dont wana give too much away.. but you are not alone any more.. you have friends to help.. which is GREAT for those tough stealth missions.
Now for the bad points.. like all ACs, this game is short.. a solid gamer with no side missions could probably complete this game in 12ish hours.. which isnt good.. it seems to be missing a lot of story.. this is the reason why it has only got 4 stars..
All in all.. a great game, and a must have for people who like assassins creed.. The campaign is very short but the missions are a little tougher and require a lot more stealth.. a good 4 star single player game.