Kristine Adams lead me to
this article from the NYTimes. Its arguing the web is already the most open and connecte social network "site."
Every link found on the open Web, inviting a user to click and go somewhere else, is in essence a recommendation from the person who authored the page, posted it or broadcast it in a Tweet. It says, “I’ve taken the trouble to insert this link because I believe it will be worth your while to take a look.”
These recommendations are visible to search engines, which do far more than just tally how many recommendations point to this or that item. The engines trace backward to who linked to the recommender, then who linked to the recommender of the recommender, and so on. It’s a lot of computation to derive educated guesses about which recommendations are likely to lead to the best-informed sources of information and then placed at the top of a search results page.
If you want to find a highly recommended article, you don't need a "like" button. Just check out the organic results of a Google search. Does the web need Facebook to connect information to people? Or does this close the already open web? I can't see Facebook arguing that it wants to create a more "connected and open" web when it has a 5,000+ word privacy policy .