Pretty much anything goes. I won’t edit comments based on language or content. If you have a problem reading the sort of filth that flows free on the internet, you’re probably at the wrong site. Try reading a feminist blog, they like to moderate the hell out comments.
I will, however, delete spam and advertisements. The spam filter for this site (and most other blogs running WordPress) will pick up anything with two or more links in it. I try to give the spam a quick once-over to make sure nothing legit was caught, but lately I’ve been getting upwards of 500 pieces of spam a day. If your comment didn’t show up, e-mail me at firstname.lastname@example.org and I’ll see what I can do.