Ahmadinejad isn't very convincing. The documents prove nothing about Iran, only that the U.S. thinks that they are a threat. But we knew that before the leak, so the leak shouldn't convince anyone who didn't believe it before.

If the leak had contained documents from Iran itself, that would have been another matter. But for that, Wikileaks would need people who could read Farsi. They would also need to have advertised that they had such people, in order to encourage leaks.