And it probably is being managed pretty well by those global mods.  I haven't visited the Altcoin section, B&H, P&S, or the Off-topic sections in a long time, so I don't have any sense of how bad spam is in those sections.  But in the sections that I do visit frequently I have seen a pretty dramatic drop in shitposts as of late.

That could be because traffic has also dropped dramatically, as I saw reported in another thread.  If that's the case, I wouldn't rule out another forum-wide infestation with illiterate garbage posters should the number of bounties/campaigns increase (and probably along with an increase in bitcoin's price as well).  Both of those factors tend to draw desperate people looking to make a quick buck without having to do much, and they more often than not don't contribute anything useful.

These moderators who "disappear":  don't they let Theymos know they're not going to be actively moderating for whatever period of time?  I get that members come and go, but if you're a moderator I would think it'd be proper to resign like you would with a real life job.