Never heard of him, but his miniseries on Jazz sounds interesting as heck. Don't know if I could/would sit through all twenty hours of it, though.
I'm working my way through The Civil War one right now, it's pretty good. Watched all of the National Parks series when it was screened week to week. It's not too hard but probably best to download and watch at your leisure. I'm not even American but his stuff really draws you in, it's presented really well, I think.