A 2-door RX-8...wouldn't that just be an RX-7?!?
Although I believe that if the RX-8 is a sales success Mazda will definately rush out an RX-7. I've read some rumours floating around that an RX-7 is already under development, but is awaiting the green light from management. And of course I think the RX-7 will boast performance improvements over the RX-8 to make it a worthy successor to the name.