He's expressed his feelings, via lawyer, about the loss. It *is* a shame the two has such a falling out but, really, like his "Groundhog Day" character Murray is kind of a prima donna jackass.
He may be a prima donna jackass, but he's also doing the best work of his life and career in those movies with Wes Anderson and any other independent director around. The thing is (to me) he didn't seem interested in doing any more Ghostbusters movies anyway, judging by the way he was in the second movie (not rearing the uniform, wooing Sigourney Weaver at a restaurant above while the rest of the guys are in a deep old subway tunnel below looking for mood slime.) As it was, and is now, I think it's a question not of if there will be a reboot of the franchise, but when.