2K Games and Firaxis have announced XCOM2 will be delayed, releasing next year on PC on February 5, 2016.
A message from the XCOM 2 development team at Firaxis Games had this to say:
Hello XCOM fans,
We want to give you an update on the release date for XCOM 2. We’ve set a high bar for the sequel and the entire team has been working hard to make sure we deliver a great follow-up to Enemy Unknown. We just need a little more time to make it the best possible game.
With XCOM 2, we want to have more depth, more replayability, and more investment in your soldiers and this extension will give us the time we need to deliver on our promise to you.
We appreciate your patience and continued support as we move towards February. Good luck, Commander!
-The XCOM 2 Dev Team