According to their press release,
Compared to the other biometric authentication techniques, vein authentication technology achieves higher accuracy on personal identification and forgery resistance because it uses the veins inside the human body. Finger vein patterns differ from person to person, each finger to finger, and it is said that they do not change over the years.I like that phrase, "it is said." That's the kind of CYA phrase you use when you're not sure.
If true, however, the FRR (False Rejection Rate) is less than 0.1% and the FAR (False Acceptance Rate) is less than 0.0001%. Sony plans to commercialize this technology within the 2009 fiscal year.
Now, I found some material on vein recognition dating back to 2006. I noted that the article indicated the accuracy was higher in part because there is no chance of a distorted image since the veins are internal; i.e., you can't give the sensor bad input simply because you didn't put your finger "just right" on the sensor.
Throwing out the devil's advocate view, what would happen if you broke your finger? Anything? A positive would be that if we're not using retinal biometrics we don't have to worry about a Demolition Man scenario (if anyone remembers that old flick).