For the past several months, British bank Barclays has been phasing out the security question in favor of a simpler system: voice recognition. The company announced today that when customers call its investment wing, Nuance's biometrics system will be listening in. Over about 30 seconds of talking with a service representative, the system will see if it can match them to an existing voiceprint. If it does, the representative will simply keep talking to the customer; if not, they'll move on to security questions or other verification.

Barclays says it's enrolled 84 percent of "frequent callers" over the past five months, and that satisfaction has been rated highly, suggesting that the system could be fairly accurate. Obviously, Barclays Investment and Wealth Management isn't a bank most ordinary people will be calling frequently. But Nuance, whose voice recognition technology is at the forefront of consumer dictation or voice control systems, could easily start building a broader base. National Australia Bank adopted a similar voice recognition tool for its customers last year.

So far, both have only added voice recognition in call centers, not ATMs or other automated systems. And for particularly sensitive transactions, Barclays will still use other security methods as well. With passwords and security questions both showing their limits, though, there's ongoing interest in biometrics as a way to replace them.