Horford should be ROY.
Yes, his points total isn't flashy, but he's a big kid, very smart basketball player, good FG% AND he's rebounding at an insane rate for a rookie (something that's being overlooked by everyone).
Durrant deserves mention because of his offensive numbers but his FG% is poor and that's not because of guys doubling or tripling him. It's because of his shot selection.
Oh, and I agree with Tommy on this one, Mike Miller is/was a glue guy. Skilled? yes. But he's a guy you want on your team like a Shane Battier, he's not a viable 2nd option imo. He's basically Mo Pete, but with his potential realized.