[jessedhillon]

One minor improvement I would make is to prefetch the backgrounds for the specific card types (Visa, MC, Amex) so that the swapping appears seamless. This is a great idea and I will totally keep it in mind for future projects.

The "flip to the other side" to fill out the CVV is great. I might provide a second button/link, appearing once the CVV is completed, that says something to the effect of "valid input, next step"

[stephengillie]

Another minor improvement (if possible) would be to load the bank's logo, when that can be determined by logo.

Great product, I'd use it if I had a shopping cart!