It may not be the iPhone game, but iPhone users can definitely get something of an AC2 fix with the Assassin's Creed 2 Experience iPhone app.
The Assassin's Creed 2 Experience is a completely free iPhone App released by Ubisoft that keeps fans up to date on the latest news, screenshots, and trailers on their small Apple device. Perhaps a homage to Apple's earlier dedication to gamers and gaming, the app also comes with slide puzzles featuring Assassin's Creed 2 visuals, with leaderboards in case you are that completely competitive that you have to be the best slide puzzler. Freak.
All of this, plus a bridge to the Assassin's Creed 2 Twitter Experience, allowing you to kill your friends over Twitter, which is a functionality I know a lot of you have been waiting for. The app is available right now. The game is available on November 17th.