My take on it is, BB doesn't get the audience it used to, so lack of interest. Facebook, Twitter, Iphones and Smart phones...I just think it's a mix of things, lifestyles change. You only have to look at the Digital Spy BB forum, it's tiny now compared to when BB was at it's height.
It's a shame that so many funny posters have gone, sadly I doubt it'a ever going to improve. 