what about the O2 sensors. If one of the two sensors on each bank wears out and begins giving erroneous signals it would likely give the same code.

Either way the sensors should be covered by the warranty and if the dealer is smart they will test them before jumping to replacement of the catalyst units.

I feel sorry for the people who don't drink. When they wake up in the morning, thats the best they're going to feel all day - former President Lyndon B. Johnson