player numbers have dropped rapidly since start of 2009.
That couldnt possibly have anything to do with the release of 5.0 could it?
That and many more reasons...

For starters the mobs were much easier to train, make money, kill, get PP, from, they weren't balanced as they were a little too easy, but what's better? easy with a nice number of players, or hard with close to no one to play with?
Also a lot of players and devs have left aswel, I am sure people will know why through many complaint topics

GMs seem to have gotten tougher/stricter/ridiculous in some cases and a lot of people are currently banned for numerous and silly reason, in which I don't think the GMs understand that people have their 'bad days' and 'are human and do stupid things occasionally', I am not just referring to myself.