Wrapped up S3 so I read through this thread. Fascinating to see much debate over whether or not Chuck was evil. Calvin made some decent arguments on hs behalf, but he really struck me as reprehensible. Waking up in the hospital his first instinct was to use the fact that Jimmy just saved his life to try to nail him. That was pretty much the final nail in Chuck's coffin for me (and it was already pretty tightly sealed). And yet, the amazingness of Vince Gilligan, I took no joy in watching him self-destruct, despite really wanting it to happen.
Chuck was the perfect bad guy. Maybe the best I've ever seen. He had all the hallmarks. He did awful things to his brother, but from his own warped perspective he was doing them for Jimmy's own good. He made you hate him, yet he was so terribly flawed you also had to sympathize. In the end the flaws, both innate and chosen, led to his demise.
And saddest of all is that his final words were telling Jimmy "the truth is you've never mattered all that much to me." I'm not sure how truthful it actually was, but that's where he left things.