The Stephen King movie is "The Dark Half". It's pretty good at turning a very staid "evil twin" story into something fairly menacing.
Martin is kind of shit, the complete lack of budget really shows, but it has a real punch. It was filmed in this run-down part of philadelphia back in the 70's and it kind of has this sense of dread and decay running through it. Again, playing with a cliche like vampires Romero actually gets some real punch out of the old idea.
I think a big motivator in Romero's new zombie flicks is that there was this sudden resurgance of the genre a few years back. He saw the younger crowd cashing in on his shtick and was like, "Let the old man show you how it's done..."
Interesting detail: He was originally set to direct the first Resident Evil movie, but was fired off the production when he resisted the studio's desire for "More action!!1!1!" His version was going to be much more true to the quiet isolation of the first game.
I have loved every Romero Dead movie...until this one...The acting was atrocious. The dialogue was terrible. The actions of the character made no sense whatsoever. The social commentary was hit over our heads at ever opportunity. I felt really sorry for George after seeing this one. What the fuck happened?