Facebook already does this by showing you only a part of your friend's information on the newsfeed, based in part at least on interaction type and regularity. G

Facebook already does this by showing you only a part of your friend's information on the newsfeed, based in part at least on interaction type and regularity. Google does this via circles. I believe twitter is not curated in that fashion but twitter has a slightly different model due to it's type of asymmetry.