Scott,
A while ago, before the USB memory card readers became commonplace, the most popular way to transfer data from a flash card to a PC was using a floppy disk adapter. It is a device which looks like a floppy disk, but it has a slot for a memory card. The drive reads the memory card data using its magnetic head. The PCs do reqire a special driver program to be able to communicate data through this $70 adapter.
I am sure those adapters are still available. It would cost Yamaha next to NOTHING to incorporate a driver for this adapter into an OS for the new keyboard (e.g. 2100). The other alternative would be to use a USB-connected flash card reader, which you can buy for about $40.
However, I doubt that Yamaha will support either (any more than they would change the design and actually incorporate flash memory for the OS). There is plenty of people here considering a switch from the PSR2K to a Tyros (or having actually switched already). By making the PSR2100 too good, Yamaha may be handicapping the sales of the higher-margin Tyros.
Just my $.02
_________________________
Regards,
Alex