He's leaving cos there are a few "camps" in this community and the exchange of words between them hasn't always been, well, very mature. I have to agree that i've noticed a downward spiral of late in the tone some people are using in their posts. What is really disapointing is that some of those people have been members of this community for quite a while and should really know better.
Unfortunately, i don't see a solution to this as the camp mentality now seems to have affected some moderators too.
Oh well, live 'n learn I suppose.