The question, "Should racism be tolerated in these forums", is a rather tricky one to answer. If you answer, no, you are safely a member of the group. If you answer, yes, you risk being considered a racist.
Despite that risk, I say, yes racism should be tolerated in these fora. I don't say that because I support racism but because I totally and unequivically support freedom of speech other than speech that endangers lives, ie. yelling fire in a crowded theater.
It is easy to tolerate speech that falls within the norms and parameters we have set up. It is much more difficult to tolerate speech that does not fall withing these norms and parameters. However that is exactly the speech that we must tolerate, not support but tolerate if freedom of speech is to be defended and insured.
It is easy to defend popular or neutral speech. It is much more difficult to defend odious or hateful speech or speech we feel is inherently wrong but that is exactly the speech we must defend if freedom of speech is to mean anything.
I have noticed quite a few anti-theist statements posted with no attempts at censorship. It seems that there is a fairly large contingent of non-theist so such speech is tolerated. How can posters justify allowing one form of speech that denigrates a segment of society while forbidding similar speech that denigrates a different segment of society? Is it because anti-theism is more popular than racism? Is it because there are more anti-theist than racist in the fora? Is is a perception that those who believe in a deity are considered fairer targets for insults?
I personally find such anti-theist posts to be hurtful and hateful. I still support the right of people to make them. Free speech is far too precious a gift to be endangered by censoring speech or posts we do not like.