I don't really get what you're saying by "recycled material" because you haven't really made any points. I mean, you can never say multiplayer is recycled because its always being tweeked... Story wise, well the story for AC is one of the best in games as whole. I dont see how that can be recycled because well...its not. Its just a continuous story showing the evolution of the characters. One that I'm thoroughly enjoying. Its what the game is, but the missions between them vary enough and add enough flavor to keep it interesting and entertaining.
I mean the only thing it has in common with COD is that they release a game every year...but thats something that should be praised not looked down on. If they were made just to sell more games then fuck them. I never would have got Revelations nor be excited for AC3. But they are all quality and come with an awesome story. Ubisoft has the resources to make an AC game every year leading up to the 2012 theme of the story.
Edit: You want to talk about recycled material...take a look at the GTA series. Thats why Im probably not getting GTA5....*waits for the riots*