Finally - A step towards possibly getting more for your money, out of your phone. Now if we can only find some way to do away with the restricted devices being sold by an unnamed company. I'll give you a hint, beach ball.
No really, hopefully this will be a step towards increasing usability out of cell phones. More-so, make it easier to make payments. No more forgetting your cash, debit/credit card, and other information you may need to make purchases. One of the biggest issues I see with this is security.
As I was discussing with someone, security would be one confusing aspect of paying with a cell phone. Obviously Japan has it down, but can the techs in the US get it too? I encourage them to try, but I'm speaking about the same company that was snooping in Facebook's business (direct link) while getting attacked from the other end - So much for paying attention to the local network. Not to mention the other company has a consistent history of playing irresponsibly.