As someone who builds recommender systems for a living, let me assure you that the output of the netflix prize was perhaps 10% of what you need to actually build a good recommendations product.
Sure, I wasn't implying eBay overpaid by 80x but 79 million dollars is a lot of product development once you've paid 1 million for a proven state of the art proof of concept.
Obviously eBay must see other reasons for the acquisition than just the tech itself.
Also, if it's also in large part a talent acquisition then they're going to paying more than 80 million since they're going to need to pay for some new pairs of golden handcuffs to keep the talent around.
