parakeet--your recently-published "new light" regarding your intentions in this thread ("My intent is to encourage those Christians who insist atheism is a faith to examine their reasons for making that claim and to provide sensible answers,") seems contradictory to the spirit of the original post, which was obviously mocking that particular belief of those people you now claim you're entreating for honest opinions--I'm guessing that's why the bulk of your responses thus far have also been humorous replies from the atheists who picked up on your tone (or serious replies from atheists whose sarcasm detectors need a tune-up) instead of honest replies from theists who hold said belief. Just an observation.
Anyway, on to my own atheistic answer:
To be a good atheist (as opposed to a mere ignorant nontheist or convictionless agnostic), it is absolutely obligatory that you make the following wild, (ir)rational leap of (il)logic:
God is all-powerful.
God is all-good.
There exists heinous evil in the world.
Therefore, God, as here defined, cannot exist.
Actually, holding as belief any equivalent (il)logical progression, so long as the conclusion is the same as above and follows logically from the premises--which themselves are either tautologies or conceded-to descriptions of God--will qualify you as one of the faithful--faith that your own mind, your own rationality, and your own comprehension of this universe is more worthwhile than blind faith in the deities imagined during someone else's drug trip.
Additionally, it helps to eat a beef and pork hotdog, with the bun, on a Friday. Or maybe that's some other club...certainly couldn't hurt, though.