My guess would be the source of posts. Looks like they post from "Twitter for Google TV" and "edent's tweeting robot", so they're probably outliers due to the v

My guess would be the source of posts. Looks like they post from "Twitter for Google TV" and "edent's tweeting robot", so they're probably outliers due to the volume of posts and where the posts are coming from. That combined with the characteristics of the text probably triggered the algorithm. That being said, it's unfortunate that this happened to them, the lack of manual review when kinds of things go wrong is shocking.