Shotcrete is not new. It has been around since the mid-60’s and outside of the pool industry is not really differentiated in how pneumatically applied concrete is referred to. Call a sprayed concrete pool a gunite pool or call it a shotcrete pool and you will not be wrong. The difference is in the process, the equipment, and the material.
Here is a quick comparison of the two, but really the only difference is that Gunite uses a dry mix where water is added at the nozzle, and Shotcrete uses a wet mix of concrete.
We usually see more shotcrete out west or down south where the temperatures allow them to work with wet material, not needing to worry about freezing. Here in upstate NY, we plan to work throughout the winter, so most companies use gunite.