A new radio ready flash
A new flash is in the works to replace the Speedlite 430EX II and could come as early as this fall. The new flash will be ready to work with the ST-E3-RT transmitter. The current 430 would be discontinued like the 580 was.
No word if we'll see a flash smaller than the 430 replacement with RT capabilities. I personally don't think we'll see the 3xx series updated to RT.