I don't think it's the forums fault. At the end of the day it's the users that ultimately make the forum. The guys that run this place seem to do a good job and already in the past month since I've been here you quickly learn who the guys are that know what they are talking about. There seems to be a decent core to the site. I'm assuming that when the forum started the iPhone 4 hadn't even been released yet so to begin with it would of just been a bunch of people all talking about how excited they were about getting the new phone... Now the phones out obviously things are going to naturally move on.
I also think that people perhaps need to learn the right section to put their threads in. There's an iPhone 4 hacking section, so why not put your jailbreak related post in there? People are just too lazy and stick things where ever they want.
I'm fed up of seeing the same questions being asked over and over again. Does no one bother to search the forum first? Obviously not as multiple threads get made all the time covering the same old stuff.