I haven't seen any that said anything like that.
From the pre release info page=>
Religions will not have bonuses (most likely the developers like to keep everything perfectly balanced because it is a touchy subject), but they will impact diplomacy. If you ally yourself with a Civilization with the same religion as yours, it will Enable you to curry favor with other like-minded peoples. However, they come with a memory, if you suddenly switch to their religion, they will not be as inclined to cooperate with you. You will need to be in their religion for a significant amount of time (From PC Zone).
So there will be no difference between them. Islam doesnt give more money, Christianity doesn't give more culture, Daoism doesn't give faster promotion to your units. It only matters on a diplomatic level, so you will pick the one that is to your advantage.
Thereby making it somewhat pointless. If all of your neighbors are Islamic there would be no earthy reason to be Buddist. You might as well insult all their mothers.