It's nothing personal TI and ftr I don't think a new ad-free awimb will attract heaps of new posters. The message board format is dying the death of a thousand cuts and from what (admittedly little) I know, the main message boards for the 'bigger' clubs attract a lot of furrin posters, something that awimb has by and large got rid of.
It has in some ways, gone full circle. I think I'm probably the only one left from near the start in '98 or so (apart from the occasional appearance from the Chief) and back in those days the messages were relatively few and far between. There was then an influx of (mostly young and some foreign) posters around the turn of the century and it has gradually tailed off since then, alongside the 'decline' of the team/AW, people generally getting bored with the board, being banned/flouncing so we're left with a hardcore of regular/semi-regular posters today. I don't think anything will change that