A Battlefield 3 book co-authored by former SAS operative turned writer Andy McNab has been spotted for pre-order from Amazon, Barnes & Noble and many other book retailers. The other co-author is Battlefield executive producer Patrick Bach.

The listing was spotted by the folks at the Battlefield 3 blog, which prompted us to do a little more digging. According to the various retail sites offering the book, it will be a paperback with 400 pages, and will be published by Grand Central Publishing.

Little else is known about the book, but the fact that Grand Central Publishing itself has categorised it as fiction suggests that this could be a novel based on the campaign mode, rather than a strategy guide.

In interviews, DICE has revealed that the single-player campaign will take around 6-10 hours to complete, but the developer has kept quiet about more specific details.

EA has also previously announced that Andy McNab worked on Battlefield 3 as a military adviser so that DICE could capture 'the authenticity and grittiness of today's war', and that he also helped with the motion capture process.

Amazon says the book should be released on 25 October, around three days before the current UK release date for Battlefield 3, although Grand Central Publishing puts the date slightly later at 1 November.

Is this a strategy guide, a novel based on the single-player campaign or something else entirely? Share your wild speculations in the forums.