Ragnarblackmane: The short version: It's by William King so it's chock full of grim people being grim and then killing a lot of things then making grim jokes about it all. Seriously though: He really manages to get into the psyche of a Space Wolf, which I feel is more difficult to do than even the typically inhuman Astartes because their chapter is so different in many ways.
You won't find the deepest character development or moral probing or philosophical treatises but then again that's not why people typically read 40k fiction ;)
You should find a grand adventure epic among the stars with gloriously gratuitous violence and suitably grandiose moments of heroism and villainy.
I think this is why I am enjoying the Soul Drinker series, it's not the usual soulless Space Marine novel (I'm not sure if you have read them but it's about a loyal group of Astartes who break from the Imperium, but not the Emperor). I prefer seeing another side to them, other than just novels with constant action, with very little else.
I guess I must not be the typical 40k reader as I prefer novels with more depth and character, like the Imperial guard novels, I love the setting and the themes of 40k and the IG novels have a very good human element to them. It's one thing to face the enemy in a suit of ceramite with a heavy bolter, it's quite another to face it with just a flak jacket and a lasgun :).
Anyway, sorry for talking books in a username thread.