On a more on-topic note we're slowly approaching 300K.

Indeed

My guess is that we're probably returning around the late 2009 levels in late 2012 or early 2013, but it will be hard to get below that with that many users logged in all the time. They would pretty much all have to start lurking without ever posting to get lower. The good thing, however, is that the spam section:whole board activity ratio has got much lower, thanks in part to upping the postcount requirement for it, and the overall amount of active projects hasn't gotten much lower.

Yeah that too. I had around 20-25% of every month's activity and it went to 2-3% I think for a while. I guess in some ways the total post rate is slowly approaching back my current activity rate. Also we have to keep in mind half of the staff turned 18 around that summer, so a lot are much busier, have moved on or are on the verge of doing so.