The current App Store proposal states that it is entirely for technical issues regarding submission to the App Store, but that seems to be a little limited in scope. Many of the questions about the technical issues with submissions are regarding developer tools or other issues that are already appropriate for Stack Overflow.
However, there are many more questions that people try to ask on Stack Overflow regarding business issues. Some cannot be answered definitively, like "How do I make money on the App Store?", but others, like "How does Apple send payments at the end of the month?" or "Do users purchase more applications on the weekend than during the work week?" can have specific, focused answers.
Right now, these questions are closed as off topic and the users are directed to Apple's forums or to the iPhone Software Business mailing list, but I could see a utility in having a place for the better of these questions to go. Many iOS developers would like to have a place where business issues around the App Store could be answered with hard numbers.
Proposal: App Store