You did a nice job of blurring the background with your exposure/DOF setup. The bird is well lit and focused. I guess technically this shot is hitting it pretty much right on. Something in the subject matter itself that is just "OK". Many, many, birds in this challenge and to score higher with a common subject is going to take something unique. JMO.
The sharp foreground and blurred background are good to frame this picture. Maybe if the bird were a little less centered (rule of thirds thing). Nice capture.
Great DOF. I'm on the fence about the dead centered aspect of the subject. Great detail and focus. Maybe get rid of some of the dry shrubbery in the foreground.
7 - Nice and simple. Criticism; difficult, but even more 'pop' (fairly good as is) make this even better in my opinion. Nice background and composition and the centering works well. Perhaps 640 height too for added impact for 'here', who knows.
A lot of people will bring up the rule of thirds here.... but I think the composition and isolation of the subject is great. subject a bit small though.