SO.HO (which stands for "the social homescreen") is a new launcher that puts your Facebook and Twitter feeds directly at the center of your device. Just released in beta, SO.HO takes the place of whatever launcher you have currently and makes the primary homescreen of your device a scrolling list of either your Facebook or Twitter feed. Swiping left or right gives you a "normal" homescreen where you can place widgets, apps and folders as usual. You sill get a dock on the main page too, which is nice.
You can tap the top status bar to quickly switch between Facebook and Twitter, and use the compose button in the top right to quickly make a post. There's a smooth pull to refresh option in both, and the views are actually in many ways nicer than the official Facebook and Twitter apps. If you're interested in SO.HO as a homescreen launcher replacement, check out the beta at the Play Store link above.