You can get a 64GB USB flash drive for as low as $30 now, so the raw price of NAND has to be less than that. I don't think Apple is paying a premium for higher grade NAND, I think the numbers are just not current.
Here's the rub though. If I understand it right, that could limit us to one exposed SD slot as the OMAP5 only allows for two SD slots. If that is the case, then using a microSD in place of NAND could seriously limit the device's computer based functionality.
I'm pretty sure it'll support at least 4 SD slots because those two SDIO ports in the block diagram can probably be used for SD. Actually, since MWeston has described a design w/internal microSD + two external microSD I'm pretty certain it can be done. Only two SD would be a major regression vs OMAP3 which has 3 and OMAP4 which has 5.
Then it should be a non-issue to put a 3rd card in instead of on-board NAND.
OPT should avoid soldered on NAND if they can because it'll make it more expensive to manufacture and maintain. Not really sure why you're happy with 64GB builtin NAND when earlier you were pretty adamant that you wanted full SD for the boot card so you could boot 128GB+..
Sure, I can clarify that.
If it's going to have NAND on the system board, fill the boat.
I want to run the OS from the fastest 'drive' possible.
Onboard NAND direct-attached to the SoC can be faster than any SD permutation.
If we're going to skip on-board NAND I would like to be able to use the fastest SD media available. That would normally dictate a full sized SD card.
So, in my humble opinion:
(64GB on-board very fast direct attached NAND + 2SD slots) > (3 SD slots) > (1 microSD + 2 SD) > (2 microSD + 1 SD) > (3 microSD) > (2 microSD) > (1 microSD)
All seemingly irrelevant given the other discussions going on that threaten to nix a CraigIX P2 from having ED & community input.
It would be interesting to see what CraigIX would come up with Vs an incremental step forward using as much current stuff as possible. There may be none, one or two kinds P2s as the road ahead appears to have a fork in it.