It's very gory (at least the first 100+ pages) - Also according to this wikipedia article (http://fr.wikipedia.org/wiki/Jonathan_Littell) , a "little" about Littell : He's of Jewish extraction but doesn't identify very much w/ Judaism (In fact he criticizes the politics of Israel). What interested him more than the Holocaust in particular was the topic of mass executions and genocides in general - He did humanitarian work after college in Bosnia - He got his degree from Yale, after spending most of his life in France, getting the bac in France.Apparently he wrote the novel in under 120 days after a few years of extensive research.
If you want to listen to a discussion where he is featured (you'll see that he speaks perfect French, and has some interesting things to say), you can click on this "Diffusion des savoirs de l'Ecole normale superieure" (The discussion is hosted by Ecole Normale Superieure) - you have to click "telecharger" and then wait for it to load - Littell starts speaking about his book about 1 hour in, so just scroll the little button over if you want to skip over Julia Kristeva's introduction (which is boring and tedious in any case)...
You can see him talk about the book - The guy is pretty bold-- he says at the ENS, with regard to genocidal murderers (of which the protagonist of his book is one), that nothing physically distingues us (that is, civilians) from them, "On est tous comme les bourreaux. On chient, on baisent, on mangent, on pissent, on respirent. On vit tous dans un corps qui ne suit pas les desirs de nos cerveaux."