There is certainly enough production value in this instalment of the series to make it worth your time and money. However, in the midst of the multitude of developers that have evidently put this title together, there is surprisingly large of amount of missteps in this game. The game has an absurdly long 'prologue' that teaches you the core mechanics so slowly that it's mind bogglingly annoying for veterans of the series. And when that prologue finally ends, all the sudden you can do a million different things and barely any of it feels like it's been taught to you - I went through a large portion of the game without fully understanding several mechanics or aspects. There are a multitude of side missions that are utterly boring and numerous mechanics that you'll barely use or completely forget about it because they are completely unnecessary or simply not fun. The story line, although interesting for the most part, also seems to make some tedious diversions here and there.
Luckily for everyone, you can avoid the boring parts and it won't detract at all from what makes this franchise great. The free-running and parkour is as enjoyable as ever (even though the city environments are not nearly as intricate and fun to run about it in as they were in AC2), and the general combat mechanics are very solid with some dynamite and brutal animations. I loved Connor's brutal and brawly fighting style, and had loads of fun with it.
Ultimately this game has some very noticeable cracks that are appearing under the game's own weight; and even the graphics engine is really beginning to show its age here; but you can avoid the boring parts and still have great experience that's certainly worth playing. Definitely still would recommend for fans of the series, however for newcomers, stay well away and start first at Assassin's Creed 2! You will have a far better time.