tedster - 5:43 pm on Jun 28, 2012 (gmt 0)
I'd say Google and Bing are both working with user metrics. Or more precisely, I'd say they are both LEARNING how to use this data, as well as what data to collect. In Google's case at least, I think they are intentionally sacrificing SERP quality in the short term so they can learn what they need to learn for the long term. They need to replace dependence on all the ranking factors that can be easily manipulated.
In fact I think this machine-learning has been going on for several years already and it's now accelerating. Someone here recently posted that "search is still in its infancy" - and it is. So we shouldn't hope for the old days, just because we like the familiar feeling it gave us. Search didn't work all that well back then, either ;)