A blog posting on BoingBoing provides further discussion as to the
inappropriate deployment and of RFID chips within the existing payment
marketplace.

http://www.boingboing.net/2006/10/23/report_contactless_c.html

The underlying point of this article is, the card schemes and banks said they are using key rotating encryption of all data between the card and the acquirer/issuer, but this is clearly not the case in many situations.

Another interesting paper is ‘RFID Payment Card Vulnerabilities Technical Report’ located at:

http://www.nytimes.com/packages/pdf/business/20061023_CARD/techreport.pdf