The knives come out: Visa, Mastercard will charge PayPal and Google for their mobile wallets

Our long, slow slog towards ubiquitous mobile payments isn't getting any shorter, and today comments from Visa show that it's going to get more contentious before it gets better. Visa's CEO Charlie Scharf said that "it is totally appropriate" to charge companies like PayPal and Google a fee when their digital wallets get used. Both PayPal and Google offer something called a "staged wallet," which means that those companies act as a kind of intermediary between you and your credit card. That theo...