One thing that has been rolling around in my head is license transfers.

Say as a current customer, I would prefer using the Mac App Store (MAS) to manage my updates. Will there be a method to transfer my current license to the MAS? I could see many customers being interested in that ability. It would also be beneficial for the real small developer who no longer wants to run his/her own store.

I could also see the other direction being of interest to users. Especially if Apple one day decides an upgrade isn't eligible to be in the store further or our right drops an app from their store.