if I can flash the Bios of a 560ti will it work?
flash the bios with what, exactly? no, it most likely won't work. you'd be better off buying a new kepler card/sticking with the current card rather than ending up with a bricked card.
you should wait for kepler to actually launch, get reviewed, get bugs worked out, drivers to mature and then make that decision. save up some money in the meantime.