It's not a very good topic, in general, is it?
That being said, I do say that I am atheist, in the context of school issues. People never try to talk to me about it.
The only person I've really discussed religion with in person is a friend who is very Christian, in the best possible sense of the word. Unsurprisingly, we see eye to eye.
(I'm ignoring my MIL's repeated statements to me that DH was Christian until I showed up. Because that's not a conversation.)