I've said this before, I'll try to sum it up as succinctly as possible:
Google's innovation was 3-fold: better search algorithms (pagerank), which did use the implicit data from the interconnectedness of the web to judge the relevancy and rank of search results; revolutionary data center ops (using commodity hardware with heavy reliance on automation); and state of the art software engineering (sharding, map reduce, etc.) The last 2 enabled the first to run efficiently on a rather small set of hardware and to scale up speed just by adding more hardware. The end result was better results, delivered faster, and at lower cost to google.
This led to a much better product for the end users (better/faster) and allowed them to acquire a huge portion of search marketshare quickly. But the low cost of operations meant that they could better take advantage of advertising (lower cost per search means that even lower revenue per search can be profitable).
Google's innovation was 3-fold: better search algorithms (pagerank), which did use the implicit data from the interconnectedness of the web to judge the relevancy and rank of search results; revolutionary data center ops (using commodity hardware with heavy reliance on automation); and state of the art software engineering (sharding, map reduce, etc.) The last 2 enabled the first to run efficiently on a rather small set of hardware and to scale up speed just by adding more hardware. The end result was better results, delivered faster, and at lower cost to google.
This led to a much better product for the end users (better/faster) and allowed them to acquire a huge portion of search marketshare quickly. But the low cost of operations meant that they could better take advantage of advertising (lower cost per search means that even lower revenue per search can be profitable).