John Gruber:

Putting Schiller in charge might be particularly good news for the Mac App Store. One story I’ve heard — third-hand at best, so take it with a grain of salt — is that it was Schiller who personally pushed for the creation of the Mac App Store, and that he convinced Steve Jobs to go ahead with it. (Jobs, so the story goes, thought the Mac didn’t need an App Store — that the existing means of distributing apps was good enough.) I think Schiller has a personal interest in seeing the Mac App Store succeed.

Seeing as how Schiller is often the one who announces new Macs on stage at Apple events, I’ve always thought of him as “the Mac guy” on Apple’s executive team. So, it wouldn’t surprise me if he was the one who pushed to bring the App Store to the Mac.