Three of the five Oscar-nominated films were all adapted from novels: Atonement (Ian McEwan); There Will Be Blood (Oil! by Upton Sinclair); and No Country for Old Men (Cormac McCarthy). Nothing unusual here; book adaptations always carry a bit of a pedigree that Oscar can't resist.
I'll let Rene Rodriguez blog about the nominations. You know, I just can't get that angry about any of them. Sure, I loved Russell Crowe in 3:10 to Yuma and American Gangster and feel that he should have been nominated for at least one of those performances, but who's going to complain about the guys who did get nominated? Not me. The Academy managed to realize that Sean Penn's Into the Wild was massively flawed (except for that nice performance by Hal Holbrook and the gorgeous mountain scenery); that's the only thing that would've set me off, that movie knocking Juno or Michael Clayton off the Best Picture list.