Bark—a plug-in for Growl (get it?)—was a collaboration between Zach Waldowski and me. The goal was to create a bridge solution between the existing Growl app and the then new Notification Center in OS X Mountain Lion. Previous solutions for Notification Center support in Growl included forwarding all notifications under the "Growl" banner. We took a new approach by allowing apps to display notifications with their own name and icon.
Notification Center has been available to the public for almost three years now and Bark has since been decommisioned in favor of the native technology.
The adorable dog in the icon photo is Riley, my amazing, adorable, and otherwise superlative Golden Retriever.