Hard to say for sure, tough camera angle. People tend to enormously over estimate bears. I would guess about #170 and maybe 5'6". What part of the country are you in?
Very hard to tell from just one picture. Also, having something to reference his size to in the picture is almost a must with bears.
I agree tough camera angle to judge size from. From this angle it looks to be a nice bear and if the cam was 180* from where it is the bear would be bunched up and look small. It's one I would like to see the head and a better look before shooting.