In the near future, where will you go to search for products, reviews or news articles? Facebook or Google? Apparently there’s a “war” going on between Facebook and Google, that might not be obvious to a lot of people. The issue: Lots of the content created on, and uploaded to, Facebook, is shielded from Google and other search engines. A Facebook-login is required to view data available to “everyone”. This means the data cannot be searched from search engines, but only by Facebook users.
Today, the Google-Facebook rivalry isn’t just going strong, it has evolved into a full-blown battle over the future of the Internet—its structure, design, and utility. For the last decade or so, the Web has been defined by Google’s algorithms—rigorous and efficient equations that parse practically every byte of online activity to build a dispassionate atlas of the online world
(Great Wall of Facebook: The Social Network’s Plan to Dominate the Internet — and Keep Google Out)
You might also find this article interesting; How Facebook is Gunning for Google (And Killing SEO)