Brotherhood, while not as huge as AC2, was a great game. There was a lot to do, far more than what most games give nowadays. And that's only speaking about the solo game.
Revelations seems lackluster at first, because of the marketting. The great trailer was full of rage and was epic, and the villain looked frightening as hell. But the game is not about some epic revenge, or some spectacular war this time. It's more about Ezio understanding where he comes from, and how he can be at peace. It's really a zen story, and in that regard, it's closer to AC1.
Both games were interesting because they added depth to Desmond as well. Brotherhoor show us how he evolved, how he's nearly ready for the war, and how he's important. Revelations helps us to understand him better, and his backstory is really engaging. I know a lot of people despise the platform stuff, but I think it's inventive, and it gives a different feelings to the revelations about his past.
Of course, these games are not as incredible as AC2 was. This one had a moving and engaging story, it was bold, the setting were incredible, you had to go in some amazing cities... and it seems AC3 will be as huge, if not even greater.
Please tell me you're kidding
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