One of the things that upset me when reading articles written by "social media experts" is how they look to established platforms, like Facebook, and derive strategic conclusions that only work for powerhouses like Facebook. Rarely will I find authors who take into account the size of a company.
With the successful proliferation of Facebook's "Like" feature on tens of thousands of websites, I'd say they now have a very rudimentary search engine which is driven by user promotion rather than (Google's) keyword ranking. Regardless, Google has some insanely smart people on their team. I'm waiting to see whether Google retaliates.