The new biometric system creates a digitised map of your face then converts that map into a hash code and compares it to the hash stored on the company's servers. This will allow users to not only make payments via mobile with their fingerprints but also by looking at the camera and blink once. (the blinking is to ensure the system that you are not a picture being held up to scam the system.)
There are reports that MasterCard already has deals ongoing with Google, Apple, Blackberry and Microsoft so that they can initiate a 500-person test program later this season. If the bugs are cleared out we may possibly expect the feature to go public by early next year.