***Have you ever lived in a Muslim country? I suggest you do before you write such nonsense about "evolution of religion"***
Haven't lived in a Muslim country, but I have visited Muslim countries. However, I don't see your point. Have all atheists lived in an atheist country? If not, then how can they decide atheism is a better belief system unless they know what living in an atheist society is like? You can do better than this kind of argument.
***If anything, Islam is the most evolved religion of all, since it took the memetic features of existing religions out of their embrionic state and took them to a new dimension. Today Islam is at the top of the religious food chain, as Yasir pointed out. If evolution continues its way, Islam will cause the extinction of all other religions, just like humans are promoting the extinction of other forms of life.***
I can't predict religious evolution. I know that it evolves and there are many factors that encourage the adoption of new memes. However, in my opinion the direction of religious evolution is to adopt 'higher principles' while discounting 'lower principles'. For example, in Isaiah the concept of literal sacrifice was seen as inferior to the concept of sacrifice of the heart. This is just one example how a religious writer took a 'lower principle' and made it a 'higher principle'. I believe world religion has evolved because of this very reason.
***Evolution and God are antagonic, and that is a fact even the most simple-minded creationist will understand. Heck, even Darwin himself realized that!***
I see things differently. Evolution is a major concept in religion, at least in the Christian religion which I am most familiar. However, in my discussions with Buddhists and Hinduists, I don't think it presents much trouble in their beliefs. As for the religion I am most familiar, evolutionary-type thinking has always been a cornerstone of New Testament teaching, it is just that biological evolution caught many Christians by surprise. Some resist to this day, but they are simply ignoring huge sections of the New Testament.
Warm regards, Harv