I would say that it's because search engine ranking is good enough. At the very least we are in the domain of diminishing returns. In terms of innovations, the

I would say that it's because search engine ranking is good enough. At the very least we are in the domain of diminishing returns. In terms of innovations, there was a weird and misguided attempt to integrate "social search" into your results, which thankfully seems to have disappeared. There is also Google's Knowledge Graph, which is a promising idea but doesn't work well yet. Search for "calories in a cup of corn" and Google's answer is wildly off. Or try "activation fee" and find out that it's $40 (huh?). It remains to be seen whether this feature can be rendered trustworthy and relevant.