Twitter is often mislabeled as a social network when it’s actually more of a real-time information network. Yes, people make connections, but they tend to connect based on shared interests and location above existing friendships. You don’t follow your friends from high school, or others with whom you have nothing in common; You follow people who have something to say. And-more importantly for Google-Twitter is the most expansive, real-time, searchable window to the world today.

Twitter and Facebook both have things Google needs if it wants to move into the post-web world. Facebook has social relevance. Twitter has real-time information. But Facebook and Google view themselves as competitors. And while Google and Twitter once had an arrangement, that deal fell through, for reasons neither party will fully disclose.