This is "Gemini Twins" from Karl Fulves "More Self-Working Card Tricks." The presentation is
slightly different, but if you know how to do that trick, you know how to do this one. Do yourself a
favor, buy that book (it's here at Penguin for half the price of this trick). You'll then know how
to do this trick and 87 others as well!
I own that book and know Gemini Twins, but if I wanted to perform this (and I might), then I would pay Robert Giobbi for his idea. It's not legally required, but it's the right thing to do to pay for a magic "play" instead of copying someone's act. This isn't a trick, it's show business!