PLEASE READ the following literature as it provides strategies for supporting an array of NAND devices available on the market today.
http://focus.ti.com/general/docs/lit/getliterature.tsp?literatureNumber=spry164&fileType=pdf
Carefully consider using Managed NAND solutions (i.e. ONFI) as this will provide greater flexiblity as you migrate between various managed NAND parts over the lifetime of your product.
If Raw NAND is preferred, pay close attention to the EEPROM solution, because it provides the most flexiblity as you migrate to various managed NAND devices