Next CX9 is coming out as 2017, not 2016.
For 2016, it is CX3 and Miata. Mazda cannot possibly push out more than two new vehicles in one year.
Also, possibly 2016 Speed3 (also w/ the 2.5G-turbo to be used on CX9, making more than 300+hp/ft-lb).
Speed6 is not likely at this point.
Diesel versions will come when they are ready for US (i.e. no comprise to performance, and no urea tank).
In short, next CX9 is probably still on drawing board and in design phase. No way you could see a prototype on the road.
Above, just my opinions. I am not an insider.