Doctorow is a "clear thinker" if you're fine with his oversimplifying matters and making a lot of assumptions about things that he shouldn't be making. He's a bit too bloodthirsty about killing copyright: he seems all-too-willing to abandon all traditions just because things are changing. I don't think that "get rid of everything" is at all a measured response to the issues at hand. Similarly, whenever he talks about art I want to jab a fork between my eyes. The guy doesn't know what he's talking about. He knows less about what he's talking about than I do on the same issues, and I'm not particularly well-versed in the subject.
His fiction is terrible. That he was nominated for awards with that one story of his just saddens me. It's cliched, poorly-written, and really not all that interesting.