Cyberbob has been banned for consistently ignoring instructions to stop trolling.
This is something that has gradually built up to the point where a ban seems like the only viable option. We gave Cyberbob ample time - well over a year - and ample warning. More than ample warning actually, as Cyberbob managed to rack up 24 warnings (I think, the forum is starting to swallow the older ones at this point), more than any other forum member since we instituted the warning system.
I had really hoped that we could work with him, but apparently that is not the case. He has been on probation for almost a year now, a fact that we shared with him in October '07. Since then he accumulated another 8 warnings, mostly for trolling. Enough is enough, and while his latest post wasn't a particularly grave offense it was trollish, and in this case it turned out to be the proverbial straw breaking the camel's back.