Two things I think Rob.
1. I'm not sure Forums are the hotbeds of activity they used to be. Compared to say ~10years ago, facebook, twitter, etc etc are much more popular and people join groups of like minded people on these sites.
2. People's situations change. I've fished once this year. Mainly because I don't have every other Friday to myself any more, the wife and the wee man are at home and I can't justify going out fishing and cycling and the odd catch up with mates etc etc. I suspect that a few other forum dudes have gone the same way. Goolager for example used to be a regular poster and he's not been seen since the arrival of Goolager Jnr mark 2.
I do like dropping in to see the big brownies and the odd silver tourist.
Cheers
Matt