If you've already read about 10 books on postmodernism and you're thirsty for more, this will make a great 11th book. It's not the easiest (try Postmodernism for Beginners) or the most insightful (try McHale's Postmodernist Fiction or Jencks's Post-Modern Architecture).
Huyssen clearly knows his stuff and has some great insights, but he spends a lot of time dwelling on the very dichotomies he claims have become outmoded. For exmple, he writes:
"...my main point about contemporary postmodernism is that it operates in a field of tension between tradition and innovation, conservation and renewal, mass culture and high art, in which the second terms are no longer automatically privileged over the first; a field of tension which can no longer be grasped in categories such as progress vs. reaction, left vs. right, present vs. past, modernism vs. realism, abstraction vs. representation, avantgarde vs. Kitsch. The fact that such dichotomies, which after all are central to the classical accounts of modernism, have broken down is part of the shift I have been trying to describe."
He sure uses a lot of dichotomies to describe the breakdown in the dichotomy system!
FYI: Huyssen is a German professor and relies very heavily on German examples.
If you're really into the topic, it's well worth reading. It's a must for theory junkies and anyone writing a dissertation on postmodernism or doing graduate work in German modernism or postmodernism.