Okay, not trying to blow my own horn or anything here, but I was there in the IRC when it happened, so let me explain what he said to us.
It was the morning after (I think it was after, it could have been the same day. I was asleep when the drama happened) Thanatos went on a Tengen Toppa Gurren Lagann spree, quoting the show every five seconds and generally annoying everyone. I got onto IRC - it was just Wily, Loaki, Ares/Alma and I - and someone said Thanatos was being annoying. I asked where and what happened, I got a link to the thread. Wily pretty quickly got really ticked off by the whole thing and, well, it was the final straw for him. He said he had had enough and he was leaving RPM. Shockwaves rippled through the IRC room, there was much pleading for him to stay, but he had made up his mind. Apparently he was already upset with recent events before that and this was the incident that just made him snap, and that it was time he focused on IRL things he said he'd been neglecting. When asked if he was going to say he was leaving, he said people would figure out when they saw he had locked his art thread. Manly tears were shed and Wily left both the IRC and RPM.
About this time, as I recall, Thanatos was banned. I talked to Wily a little while later, asking if he ever intended to come back, and he essentially said yes, eventually, after he had taken a break and sorted out some things in his life that needed seeing to. He's still around on MSN (and presumably Skype, but I haven't checked) every so often, but he doesn't seem intent on returning anytime in the near future. Eventually, yes, but probably not for a while at least.
Now, bear in mind that I can't speak for the good Doc. I'm only citing what happened that morning on the IRC. If you want to talk to him yourselves, well, it's neither my place to say you can or you can't. All I can suggest is that he be given some time to sort things out and have a chance to think and reflect. I don't know if he wants to talk about it or not. I haven't brought the subject up since.