That was an absolutely atrocious call. I replayed it for my wife about five times to demonstrate what home-cookin' looks like. (She went to OM, however, and was unimpressed.) My six-year-old thought it was pretty bad, though.
I hadn't realized that he was in the end zone when he threw it because the TV camera was behind his back. One of the refs tossed the flag, but I thought it was going to be for intentional grounding--until they waved it off.