@MRC @Gargron There are quite a few bits around, but most of them do cross posting with other sites or work as an RSS feed. I haven't seen any problematic bots yet.

They could very well appear (or be here already), but with the way content is shared and moderated on Mastodon they are much less likely to have any reach. If a server fails to moderate and becomes a haven for trolls and spam, the entire server can be blocked either by the other servers or by individual users. :)