It’s up over at the Grantland blog:
The route concept the Bills used on the play is an old West Coast offense staple: the “drive” concept. On the play, the outside receiver, usually in a short motion (just as Nelson was) comes in motion toward the line of scrimmage and runs a crossing route. An inside receiver will push straight upfield to 10 to 12 yards and break across (on this play, the Bills used a man-to-man technique where the receiver turned outside but pivoted back inside), while a third receiver, in this case the running back, ran to the flat.
Read the whole thing. I should have a longer feature up over there later this week.