Not an entirely new idea (Score 2, Informative)

The idea of using randomness to get better survey results is not a new one. In his 1990 book "Innumeracy", John Allen Paulos posits a system for asking a potentially embarrasing yes or no question whereby the examiner asks the subject to flip a fair coin before responding. If the subject gets heads he should give the embarrasing answer, tails he should tell the truth. The idea is that the subject is then spared the trauma of giving the embarassing answer since the examiner is not told the result of the coin flip and it is possible the subject just flipped heads. Knowing the "probability distribution" of a fair coin it can then be assumed that half the respondants gave the embarrasing answer as a result of their coin flip. These can then be removed from the data leaving a staticically accurate result.

It seems that what the IBM folks are doing is a staightforward extension of this idea to a larger response domain (numerical ages as opposed to boolean questions) and to a more automated system in which the website flips the coin for the subject and amends his answer accordingly.