I wonder why. From Newsbiscuit:

PepsiCo have announced today that they are terminating the current contract with Dr Rowan Williams, Archbishop of Canterbury as the face of Pepsi Cola. The brand will now be moving away from the centrist Church of England image, in which Pepsi drinkers were portrayed reflecting upon difficult spiritual matters as the product is remarketed ‘in more of a hip hop direction towards youth and music’.

Although a number of global brands have previously benefited from major celebrity endorsements, PepsiCo have had been forced to admit that choosing an elderly Anglican archbishop has not provided the massive boost that they had hoped for. ‘Oh it’s very easy to be wise after the event’ said Pepsi Co’s Head of Marketing Chad Taylor. ‘Suddenly everyone seems to be an expert in celebrity endorsement and claim they knew this would never work.’