Why not!!!
BG has it's own fans, and there can be very different storylines. It could be that Black Isle leaves the project like Van Buren. But that means not there will be not a BG3.
I like'd the first two, and will also buy the 3. one (if it happens). I enjoyed them much much more as NWN. Hopefullyit would not take long for the new game (like Fallout3)...