Jason at Xbox365 has written a short review of the Halo prequel novel, The Fall of Reach by Eric Nylund.
Unfortunately, he seems to be laboring under a serious delusion-- namely, that Bungie's game was based on Nylund's book, rather than the reverse:
Ever wondered where the cool storyline in Halo comes from? Did you really think that the dudes at Bungie & Microsoft came up with the Covenent, MasterChief and the curvy Cortana? Think again. Halo, The Fall of Reach is the original book from Eric Nylund that introduces Halo, and it's amazing powers.
Of course, if he'd been following the progress of the book from the start, or had read any of the forum posts by Eric Trautmann at Microsoft, he'd know that Nylund took Bungie's material and made a novelization out of it instead of the other way around.