I cut-and-pasted the AGS forum stats into a Google Spreadsheet and generated some charts. They show that while the amount of posting in the forums has had a small downward trend over time, the actual number of people registering and online has been steadily climbing. So the forums are accumulating more, less chatty people.
The cool thing with these charts is that they are dynamic, so if I update the spreadsheet (and, that's a big if, admittedly!) then they will be updated. Cool as mince!