OK, this is VERY unscientific, with a huge selection bias, but I thought that I would look at this thread to get an estimate for the breakdown originally asked by the OP. Obviously, to do this I have had to infer people's "status" from their posts, and I might be off base for any one of these people.
As the old joke goes, how do you tell if someone is an atheist? Don't worry, they will tell you!
But in actuality, I find this not to be the case. Atheists have a pretty poor public image, and most of us don't really want to get into public debates about it unless there is an overriding political issue (like church and state stuff).
Maybe atheists are more likely to respond to a thread like this? Maybe most Christians don't like to proselytize as much as we think?
Anyway, this is what I got:
Theist posters: 7 (20%)
Atheist, agnostic or anti-theist posters: 17 (50%)
Unclear / off topic responders: 10 (30%)