We can expect that Facebook, like Google, will use its stash of data in ways that are wonderful and in ways that are creepy. This is the double-edged sword of a digital life. Big companies are tracking you all the time, and they're doing a lot of things you don't like with that information—including serving you ads. But all the data is also extremely useful; Google and Amazon, for instance, are powerful precisely because they know so much about you. It's only by keeping mountains of data that Google can predict when flu season will start or describe the traffic conditions on your morning commute.
Facebook will surely find ways to make money from all the data it collects. The more you click "like," the better for Facebook to serve you ads tailored to your preferences. But Facebook doesn't have to limit its ads within its site. The company is already using the new plugins to allow third-party sites like Slate to get deep demographic data about the users who visit their pages. It's not a stretch to expect Facebook to build its own behavioral advertising network, a system that lets sites target ads specifically to you.
It would be a mistake, though, to dismiss Facebook's system as merely an effort to squeeze revenue from its members. This is more than about money; it's also, as Zuckerberg says, about building ever more useful online tools based on social data. Right now, we can't possibly imagine all the great things that can be determined from this data, just as it was impossible to predict, at Google's founding, that the company could one day use our search queries to forecast flu season. But brilliant innovations are surely coming. In particular, all this information will help Facebook and third-party apps tease out relationships among people, real-world items, and specific pages on the Web. Armed with this data, we can expect better movie-recommendation apps, better dating sites, better online games, and probably a lot more.
At the very least, it will soon become possible for Facebook to build what has been a holy grail for Web data fiends—a "semantic" search engine. Every time a developer adds a "like" button to a Web page, she gives Facebook a little bit of information about the kind of data represented on that page. For instance, as IMDb adds "like" buttons to its pages, the site will tell Facebook which ones represent actors, which ones are directors, and which ones are movies. Facebook will thus get a tiny bit smarter—it will be able to tell the difference between The Rock and The Rock. That might not sound like a big deal, but this is exactly the sort of information that Google spends all its time building algorithms to try to determine. Now Facebook will get it for free, from Web owners themselves. Facebook will also be learning about you, and thus it will be able to guess, based on your profile, whether you're looking for The Rock, rock music, or rock formations.
Is Facebook now poised to topple Google in search? No, likely not. Not soon, anyway. But by extending its tentacles across the Web, Facebook is now primed to make itself as ubiquitous and essential as Google. The world's biggest social network won't be going away. Rather, it's refashioning the Web in its image.