That title is such a tease, man
The Pokemon anime has been running for 19 seasons -- wow, I must have missed a few here and there. Series three of the X & Y saga is coming soon, and will be titled "XYZ," continuing the adventures in the Kalos region.
XYZ will premire on Cartoon Network on February 20, 2016 at 7:00 AM ET. It came out last October in Japan. At this point people have probably given up on a Pokemon Z, but since the latest generation was my favorite, I'm still holding out hope. Maybe Nintendo is waiting for a rainy day (when 3DS sales dip down the line).