I've watched some Yankey and I see what Jeremiah is saying a little, but honestly I liked what I saw. He seemed quick to fire off the ball, good balance, looked like he did his job. He was slow, and looked to have a hitch in his step (didn't look smooth) when pulling, though.
I prefer Brandon Thomas. I watched his game v. Ohio State, and he really plays physically and can create push in the running game. That guy is going to be a high caliber starter at OG for someone. Really wouldn't mind him at #47, if he makes it there.