I got through the first half last night, and watched up to Lothlorien this morning before work. I love it so far. It's like a snowball rolling down a presumably snow-covered mountain. They start off small and gain momentum as it goes on. By the time the movie gets to Rivendell, they were firing off one solid riff after another. The Council of Elrond (Hubbard) scene is particularly hillarious.
So far, my favorite riff is "4 and 20 blackbirds, baked in a DIE."