I just got back from a lecture here at my university by Joseph Tate, a scholar who has studied the lyrics of Radiohead very closely using methods of literary criticism. It was fascinating to dig into some of the songs and see them from that kind of perspective. I took my best friend along with me, who is a complete music nerd, and we agreed the lecture would have been helped by pairing the literary and lyrical criticism with musical criticism as well.
Tate is the author/maintainer of this site:
http://pulk-pull.org/radiohead/ which is a blog cataloging references Radiohead make in their music and videos to literature, art and politics. He is also the editor of a collection of essays about Radiohead that is coming out this spring.
He finished the lecture with Arpeggi and I have to say I loved it. The first section reminded me of church bells. So beautiful. My friend went into nerd-mode afterwards and analyzed the song from the musical standpoint. Both of us were very impressed. At one point I remember looking over at him and he had his eyes closed, obviously off in his own Radiohead-land. And they are that kind of band that pulls you away and into the other. Definitely.