Inception: One of the best new films I've seen this year, a modern take on the sort of reality-bending issues explored by the likes of McGoohan and Cocteau, and in print by some of the best New Wave science fiction, with a cleverly ambiguous ending. Also, the less cute Leonardo DiCaprio gets, the more he actually shines as an actor, here brilliantly portraying a man slowly going mad in a series of dreams within dreams.
There Will Be Blood: Takes several familiar tropes of frontier fiction-- the small wilderness settlement caught in a power struggle between big business and a small community leader, the father and son becoming estranged and reconciled, the unexpected arrival of the long-lost relative who may not be all he seems, the up-from-poverty entrepreneurial life history-- and plays with them to explore the complex dynamics between an oil prospector, a pentecostalist preacher, and the oil prospector's son (or maybe not, it's complicated). I'm not really certain it deserved all those awards/nominations, but certainly it's got a lot going for it.
ETA: Alan suggested a somewhat more complicated subtext exists in TWBB, in which Daniel Plainview is the devil, hiding in plain view (Daniel being a reference to Daniel Webster); first seen in a pit, mining for silver, he then becomes an oil man, leading Paul to sell his birthright and Eli to become tempted by the sins of pride and avarice (note that, like Jacob and Esau, they are twins), leading the latter to deny God in the end; HW, however, ultimately rejects his father and walks away from temptation. So perhaps it did deserve all those awards, and thanks Alan for seeing what I didn't.
Movie count for 2010: 90