If they don't get stuck on the exact implementation of Coin and focus on meeting the now identified need of consumers to have a simpler way to carry and use credit cards using all kinds of possible techniques, they can grow this into a real business. They have our ears, and some of our dollars. They have a community. What do you have?
That is the real genius of Coin - they tested and identified a need that many questioned especially since very large companies have tried to build "Wallets" (looking at you Google) without success so far. They have given themselves (and others) an indication of what consumers want - we want our wallets to be simpler, slimmer and 100% compatible with existing systems.