Circle(
https://www.circle.com/en) is an easy place for Americans to buy and sell Bitcoins and easily transfer to and from your bank account. They are well funded and it's run by professionals, super simple to use for new users - appears to work in USD with Bitcoin 'under the hood'. Should be easy enough to learn to use for most folks using the internet and shopping online already. Problem solved
Visa and MC just strengthened that which threatens to make them redundant with this move.