Torontograffiti.com were the ones who provided Yahoo with the artist (SKAM) and the DJs (Serious & Dopey). You can see more of their OMG Yahoo work at the following link:
http://torontograffiti.com/2011/09/10/yahoo-omg-promotion-at-dundas-square/for sale if the right offer comes along - Oh My God, what timing! Apparently Ms Bartz said the Yahoo Board of Directors was a bunch of 'Doofuses'.
I think it's an invisible James Bond on the purple carpet.