Eddy Cue's Answers:
1) "Because the Apple TV is not a general purpose computing platform. Too many developers would create garbage apps that don't fit in the "channel" metaphor of the Apple TV OS, making it confusing. Besides, Apple TV already supports the legion of apps on the App Store, via AirPlay."
2) "Because no one actually thinks "it's all just content" unless they're thinking at a high level of abstraction. We can't make every single content producer create an app for every single piece of content. Can you imagine how terrible it would be if your library of hundreds of albums were actually hundreds of disparate apps?"
3) "Kara, Walt...are you two high right now? You know YouTube, Vimeo, and others already run on Apple TV, iOS, and browsers on Mac, right?"
4) "Okay, no more questions, these two are definitely high. Let's go, Craig, don't answer anything."
It's a shame, too, because the questions for Craig were a lot more reasonable.