At least some Best Buy stores are holding back stock of the iPad 2, according to reports. One source claims that the retail chain has had all stock except for demonstration units pulled. Another initially explained that Apple was upset with an alleged Best Buy policy, in which customers would be told there were no iPad 2s in stock when in reality a store had just reached a daily quota. Apple COO Tim Cook was said to be directly involved in resolving the situation, information supposedly backed by an Apple representative at a Best Buy outlet.