Because all of the social homescreen widgets out there suck, and I hate opening the Twitter app. The default FB and Twitter widgets aren't even scrollable.
LauncherPro has a good one but it only works if you use the LauncherPro home screen, and it is constantly unresponsive. (It must be doing DB/ network fetching in the UI thread... Naughty!)
So naturally, I write my own.
I will probably release this on the Play Store, maybe free with a paid version that supports more services (Facebook, Instagram, etc.)