The porn sharing site Pornhub has issued a press release claiming CBS rejected their SFW commerical for the Superbowl. 

I imagine they never thought CBS would accept the spot, and probably had no plan to pay the 4 Million that it would have cost for the spot to run during the game.

At the end of the day, this is a publicity stunt for the site, and getting people like me to share it online.  Read the article from the Huffington Post

To me the ad is pretty funny.