Anything that violates any of the other site rules, particularly those regarding mature/inappropriate content (anything in excess of PG-13 ratings). Other things that would be a concern include (but certainly aren't limited to) profiles that include on-site cheating (like the Bones solution), links to sites which would violate the rules (referral links, links to adult websites, etc.), pages containing hatespeech, and that sort of thing.

When in doubt, feel free to submit a ticket anyway and let the staff sort it out. Better safe than sorry. :)