The Cost of Victory was just uploaded to the various sites and should be available within a few hours. COV is the second book in the Crimson Worlds series and the follow up to Marines.
Marines was very focused on the early career of Erik Cain, but the second book expands the viewpoint, introducing a number of new characters and looking more broadly at the Superpowers and their struggles. I've always enjoyed science fiction with rich backgrounds, and that is what I try to write as well, so COV takes a closer look at the Crimson Worlds universe.
I'm busy finishing the third book, A Little Rebellion, which will be released in December.