In the Blink of an Eye: A Perspective on Film Editing (Revised 2nd Edition) by Walter Murch
This book was recommended in an aside in the DV Rebel's Guide and since editing is the area of film-making (other than, say, scoring) I'm most insecure about, I thought it'd be worth a read.
The first part of the book is a long essay, adapted from a 1988 lecture, on the nature and philosophy of editing. The second half is a discussion of the difference between analog and digital editing -- Murch knows this terrority well, having won the first editing Oscar for a digitally edited film.