Go to the following links for more info of this second book of the Forerunner Saga.
Excerpt 1: http://www.tor.com/stories/2011/12/halo-primordium-excerpt
Excerpts 2, 3, and 4: http://halo.xbox.com/blogs/Headlines/post/2011/12/28/The-Halo-Bulletin-122811-Exclusive-Book-Excerpt-Primordium.aspx
Primordium will be released officially on January 3, 2012, just days away. You can order from Amazon.
Hard Cover: http://www.amazon.com/Halo-Primordium-Book-Forerunner-Hardcover/dp/0765323974/ref=sr_1_1?ie=UTF8&qid=1325230623&sr=8-1
Kindle: http://www.amazon.com/Halo-Primordium-Forerunner-Hardcover-ebook/dp/B005FWOS8I/ref=sr_1_5?ie=UTF8&qid=1325230623&sr=8-5