Wonderful, Frownland. I've got the 50th Anniversary Edition of Silence: Lectures & Writings on my shelf, as well as the follow-up - Empty Words: Writings '73-'78.
I love the dedication -
To the students from the school from which we'll never graduate.
Other recent reads include:
The Rest is Noise by Alex Ross (A must-own)
The Art of Noise: Destruction of Music by Futurist Machines
(the first-ever English compilation of the Futurist manifestos)
The 17 by Bill Drummond of the KLF
The Manual: How to Have a Number One the Easy Way by the KLF
KLF: Chaos, Magic, and the Band Who Burned Pounds by John Higgs
(a book about so much more than the music)
Krautrocksampler by Julian Cope (sadly only a PDF. One day...)
The History of Jazz by Ted Gioia
The Penguin Guide to Jazz (a handy reference text)
Listening Through the Noise: The Aesthetics of Experimental Electronic Music
Democracy of Sound: Music Piracy and the Remaking of American Copyright in the Twentieth Century by Alex Sayf Cummings
How Music Works by David Byrne
Audio Culture: Readings in Modern Music (I absolutely LOVED this)
Modulations: A History of Electronic Music: Throbbing Words on Sound
American Minimal Music by Wim Mertens
Cowboys and Indies: The Epic History of the Record Industry
and Simon Reynold's Retromania (an interesting musico-cultural study)