Given Twitter's enormity, stability (sort of), and legacy, you'd think it'd have its mission and vision down to a 'T' by now. But if co-founder and board member Evan Williams is to be believed, the social networking giant is undergoing a phase of introspection and self-discovery. Heck, it isn't even a social networking site anymore. According to Williams, has figured out that it is, more than anything else, a real-time news platform. It's a change in definition that opens the doors to possibilities, including a better relationship with app developers.