It depends on how 'hard coded' cygnos is to it's onboard NAND, if it's just handling switching chip select or chip enable and giving direct leads to the NAND it's quite possible a swap may be do-able (though I can't see any reason why they'd use an ASIC to do this?) - but because cygnos2 is meant to be able to access both NAND from USB, then it is likely a question only cygnos could answer on that one.
Keep in mind, there is much different electrically/internally between 8-16-32-64M NAND and the much larger 256-512M ones, first but not least is a huge difference in internal page size and spare layout. Adapting pinout could be the easy part.
This post has been edited by cory1492: Sep 14 2009, 07:08 AM