They did offer a defense: it's the customer data. What happens is even if that customer data is only weighted as 0.001% as important as their other metrics, if that customer data is the ONLY data they have for these bogus search terms, this would happen. Google used obviously bogus search terms which have exaggerated the weighting of that data. In reality, that data might only move a page up or down a ranking on page 10 of a real search on Bing for all we know.
Unless they come up with some actual evidence of real copying, this is a non-story. The #1 complaint around here all the time seems to be that Bing ISN'T giving the same results as Google so obviously that customer data isn't be weighted as important enough!