From an FP email:
Retired U.S. Army general Michael T. Flynn, the outspoken and at times controversial former director of the Defense Intelligence Agency, has signed a deal with St. Martin’s Press to write a book entitled “The Field of Fight: How We Can Win the Global War Against Radical Islam and Its Allies,” due out in July 2016.

In a statement that came with Wednesday’s announcement, Flynn said he’s writing the book “to show that the war is being waged against us by enemies this administration has forbidden us to describe: radical Islamists.” He also wants to “lay out a winning strategy that is not passively relying on technology and drone attacks to do the job. We could lose this war; in fact, right now we are losing. The Field of Fight will give me [sic] view on how to win.”
I did note, probably a week ago, some hostile tweets that he had had appeared on RT as a "talking head".