Not just offensive production, d'Arnaud was the 2011 defensive catcher of the year in the minors and has a career .990 fielding percentage behind the plate versus .985 for Norris. Prior to d'Arnaud's injury this week the two players have played almost an identical number of games since both starting their careers in 2007 (486 norris vs 483 d'arnaud). So maybe you think Norris is better because of his sweet beard or that someone being barrel chested makes you more durable? I would put them as close to equals behind the plate and give a significant edge to d'Arnaud at the plate.
Regardless, both great young talents, glad the A's stepped up and gave Norris a shot so soon. Hopefully he continues to make the most of his opportunity.