Here's a look at Ginn's end around. As you see from the first shot, the Dolphins did nothing to make the Bills think this was anything other than a base offense - would they run or pass?
At the snap, Henne drops back, but Ginn then circles around behind him. Henne pitches the ball to him, and Ginn goes up the field. Look at the line blocking scheme - this is a well-designed play with the blockers opening a whole and trapping several players on the right side as Ginn went left.
In the second shot, you can get a sense of where the blockers went on the play.
And finally in shot three, take a look at Ginn's decision. He could have turned out behind Donald Thomas, and used his speed to get beyond the tacklers. But he chose to go inside, which brought him into a couple of tacklers. IMHO, the blockers were blocking to give Ginn the sideline.
And firther IMHO that's why Ginn is not having more success. His decisions on routes and runs shows an "immaturity" in the way he handles himself.