Hang on, seems like you guys missed out the real fun in this story
Q: How and when did Cisco find out about this issue?
A: Cisco first became aware of this issue in December 2010.
And later:
Only in late 2012 did field failures and supplier review data point to a potential customer impact
So it took an engineering company 2 years to figure out it was bad memory, and the same time frame to admit to customers they were exploring an issue (They denied all knowledge until this PR stunt was ready to be pushed out the door).
I dont know about you, but that seems like a very long time, a significant portion of the shelf life of most of these products.