About why religion is most certainly not a sure bet. It's long, but, I think, a well-stated set of arguments. The first one points out a glaring problem with belief in the supernatural.
The first and most obvious problem with Pascal's Wager? It assumes there's only one religion, and only one version of God.
How do you know which one to wager on?
The differences between these gods and religions aren't trivial. If you obey the rules of one, you're guaranteed to be violating the rules of another. If you worship Jesus, and Islam turns out to right -- you're screwed. If you worship Allah, and Judaism turns out to be right -- you're screwed. If you worship Jehovah, and Jainism turns out to be right -- you're screwed. "