I have noticed that some of these spam threads have been tagged according to the event that they are advertising. I was under the assumption that you had to have 300 posts under your belt before you gain the ability to tag posts, so either the spammers are circumventing this prerequisite or an insider, a TMO regular, is responsible for these tags. If it's the former then I don't think anything needs to be done (as it's no big deal, once the post has been deleted it's gone) but if it's the latter, then surely that poster is the person behind at least some of the spamming.