^ I was thinking they can just reuse the camera module from the 1020 or the 808 without adding anything to it. At this point the R&D and the manufacturing of the module is scaled to the point where they are probably making money on every device, so they might be able do it without any losses. The initial R&D investment is where the real cost for it came from, and I am not sure if they made any money on the 808 to be honest.. the 1020 is a different story, they've probably sold way more 1020s then they did 808s.
If I remember correctly you can buy a replacement camera module for the 808 at around $50 .. so the manufacturing cost must be much lower if a third party vendor is selling it for that price.
Now if they start adding new stuff like you say.. that might come later in the year as the next camera flagship.
I am talking about an upgraded 1020 .. call it 1020s ; )