edit: Profile comments (I still count those as post)
So we had a spammer slowly crawl over 200 profile. They couldn't post any links because I have an add-on preventing newbie without X amount of post from posting links (http://xenforo.com/community/resources/sonnb-stop-spam-here.1086/) and thank God for that, because after posting on over 200 profiles I'd still call that successful & can only image how much worst it could have been.
This was a human spammer. Since they made comment in relation to other people. I can only image what a bot would have done.
So I started asking myself, how did I not notice him crawling all over the site, posting on people's profiles. The answer is that the recent activity does not seem to count profile post. And so it seems to be a free range way of basically having at it.