It's called The End of All Things, and it's book six in the series (here's my review of book one); he's touring it all over the USA.
Some reviews:
"Polished and powerful…The inevitable and parallel downward spirals of the two corrupt space empires, the human Colonial Union and the alien Conclave, are finally coming to a head. All four protagonists work for one of the two entities, and Scalzi shifts among their perspectives to thread a fine needle, recognizing that good people can be entrenched in terrible systems and sometimes can't (or won't) change them."
—Publishers Weekly (starred review)
"It's classic crowd-pleasing Scalzi, offering thrilling adventure scenes (space battles, daring military actions, parachute jumps through a planet's atmosphere), high-stakes politics, snarky commentary, and food for thought. Delightful, compulsively readable, and even somewhat nutritious brain candy."
—Kirkus Reviews (starred review)
"[F]ascinating, uncharted territory for military science fiction. The world is a considerably complicated place, and this is a book that recognizes it, and attempts to capture a tiny piece of that complexity. The format of the book, with its four parts and sub-chapters, aids the narrative in this regard, reminding me of the films Syriana or Traffic by telling huge story in tiny brushstrokes….[T]he series has been left in a good place, and I can't wait to see what happens next."
—io9.com
The End of All Things [John Scalzi/Tor]
(via Making Light)