We’re working on a more serious spam filtering system.
We may add a report posts button but it wouldn’t actually be that useful for spam because admins already see a list of all new posts (which we need to review anyway for front page). Having people report them wouldn’t help us address them any faster.
If our new spam filter is insufficient there are some other options that I think would help more (such as giving high karma users the ability to delete spam directly)
Prevention over removal. Old LW required a certain amount of karma in order to create posts, and we correspondingly didn't have a post spam problem that I remember. I strongly believe that this requirement should be re-introduced (with or without a moderator approval option for users without sufficient karma).
Yes, that means spam just shows up regularly in the All view. (In general, changes made to LW views do not affect greaterwrong, although views based on manual-curation still work because we don't put spam on frontpage or curated)
The initial version of the "must be approved by admin" filter just applied it to the LessWrong frontpage views (among other things, because we wanted new users to at least be able to find their posts on their personal page).
The upcoming patch moves the filter into the default view (so it'll affect GreaterWrong), and then instead manually removes it from the user profile view.
The spam filter in general seems to be working okay-but-not great (part of why we went ahead and implemented the "must be approved by admin" requirement)
Admins receive notifications for all new users so going forward I don't expect spam posts to be too much of a problem.
We haven't yet implemented the "admin approval" requirement for comments, largely because there isn't currently a wave of comment spam so we just haven't gotten around to it, but if comment spam becomes a problem we'll prioritize it.
"Having people report them wouldn’t help us address them any faster." - Perhaps you could allow high karma users to cause these posts to immediately be hidden? That would be an intermediate step between allowing them to delete them (Although you'd also need a way to remove this capacity if it were being abused)
I've been seeing quite a bit more spam to the site recently. It might be worthwhile to add an option to report spam instead of the current situation where we can only downvote.