Artistically this would be a challenge for any artist. When I saw this video I started thinking of having to deal with proportion while being so close to the drawing surface.
I think this is a cool marketing idea. Not only does it get people talking, like myself, but think of all the people driving by while it was being completed.
I tried searching to see who the artist was but I couldn’t find anything. If someone finds out, please let me know.
Update: A friend, Rafael Rizuto (http://www.rafaelrizuto.com/) told me that Sasan Saidi did the billboard. You can see more of Sasan’s work on his website (http://www.sasanpix.com)