As seen in the (long!) thread on Atheists on the Planes, the book A Guide to Hell asserts that Asmodeus devours the soul of those lacking in belief. Several folks have asserted that this means he gobbles up Atheists, and that the writer of A Guide to Hell was just being prejudiced... but a carefull reading of the test offers an alternative. It actually states that he received the souls of those who believe in NOTHING, not even themselves, whereas most Atheists believe in SOMETHING or other, just not the true divinity of the Powers! So most Atheists would NOT quality as Asmodeus-chow, nor would most Athar... yes, the book states that Asmodeus sometimes provides covert aid to the Athar, but I would argue that Asmodeus is mistaken if he thinks that the Athar believe in nothing or that aiding them will somehow garner him more souls...
Asmodeus, unbelief, and Atheists...
Hmmmmm,
Strikes me, that if a soul has no supernatural agent to protect (or even stand up for) ones soul after death. Then that person would be fair game.
Easy pickin's so-to-speak.
Ugh, is this thread still going on?
"All atheists go to zee DEVIL!!!"
It's a shame that this crap has been forcefully interjected into some D&D setting rulebooks. I shudder to think of what 4e will bring to the cosmology.
It's a topic that keeps popping up one way or the other as new posters discover the same canon material. Looks like the older thread is still up - and it's a worthwhile read. Amazingly enough our forumites managed to hold a conversation on the subject and *not* require extensive moderation to sort out the fights. 
True, true.
I blame the fact that there are practically no religious fundamentalists within the D&D community (for obvious reasons) and thus everyone could sympathize with the atheist perspective to some degree.
It's quite possible - though I do know some players who are strongly religious, they're also caring and compassionate human beings on top of that. (Yeah - I know some awesome people. ) I suspect that's part of what is going on, and it really makes me proud of the community here on these boards at times.
Oi vei! Here we go agian. This has been discussed to death in this old thread. I believe, if my memory serves me correctly, that the final general consensus was that that particular passage in Guide to Hell was not entirely canonical. It was intended to say that atheists (not just non-believers) are devoured, and this is why Asmodeus supports and later eats the Athar. It was all some lame attempt to do precisely what WotC is doing now, convert certain aspects of the planes to match the better known Christian mythology. Suffice to say, it wasn't accepted with applause. I think we sort of agreed that if (and a very big if at that) Asmodeus was some sort of proto-being that managed to devour the souls that have no place on the Outer Planes, it was only those souls that had a potential for belief but decided to waste it utterly and believed in nothing (as you suggest). It's all really a moot point, however, since the Asmodeus/Jazirian theory is canonically theoretical at best.