It's worth pointing out that Genesis 1 as Ancient Cosmology (Eisenbrauns: 2011) is the more robust academic argument of John Walton's The Lost World of Genesis One (IVP: 2009). The latter book was quite popular a few years ago, but I don't think too many people were aware of the Eisenbrauns volume that followed it. Both are helpful in their own way, but if you are interested in following Walton step by step as he develops his theory on the Genesis creation narrative, Genesis 1 as Ancient Cosmology fulfills that need aptly.