Even assuming 20K volumes:
Current market price for 4GB of flash is about $2.50[1]; 512MB of RAM is about $2[1]. Processor -- even if something like A33 -- would be about $4. You have another $2 of regulator, connectors, etc. The PCB is about $1.75 in volume and assembly would be $1. That's $13.25.
Even if somehow they manage to make this thing really really cheap and get below that price, let's assume $7 or 50% of magical discount on top of current volume pricing, that's not much margin. Even if you sell 100K of these a year (which is very high) you've made only 200K in profit!
EDIT: I forgot about BLE+WiFI -- add $4!
Some are saying PCB pricing is high: I'm basing that on 2.3"x3.3" 6 layer board with 8 mils holes, and 4 mil clearance and ENIG finish.
[1] I'm basing this on recent 50K purchases but here is a more public source: http://www.dramexchange.com/