Babbitt always inspires debate, especially amongst musicians and theorists: is he a bold radical, is his music sterile, is he the future, is he ruining music? Who can say? Ultimately, you'll need to make up your own mind and what better way to do that then with this handsome edition! I've read six or seven thus far and have formed the basis for a number of conclusions.
I believe Babbitt was a brilliant theorist and his work with pitch class theory was seminal in developing serial music. However, his music seems to lack something when I listen to it. It's mathematically complex, formally advanced, and fascinating to analyze; but it doesn't seem to have the passion of Berg or the beautiful mixture of formal perfection and expressive texture of Webern. While I don't particularly "enjoy" his music, I completely respect his ideas and I know music has benefitted from his work.
The only reason for the digression on my take on Babbitt is because I formed this opinions reading his work and listening to his music. I would encourage everyone who his passionate about 20th century music to give Babbitt a chance: read what he has to say about music - it's profound. If you don't like his music, simply consider his ideas and you will see how they are at work in many current composers.
Before I wrap this up, a few words on his style: Babbitt's prose is unwieldy to say the least - half page sentences, needlessly complex sentence structures, awkward wordings, it's all here. I've read widely in aesthetics, philosophy, and musicology and one can quickly tell when a complex style is necessary (Lacan or Deleuze) and when it's the fault of the writer (Hegel never claimed to be a good writer!). Perhaps Babbitt is, at times, being deliberately obscure, but I feel that he simply isn't the greatest at explaining ideas in a way that leads to understanding. There were so many instances where a paragraph could be half the size while still conveying the same meaning - it's actually that bad. Oh well - maybe this is part of the fun. It definitely WAS amusing at times and in all honesty, it's not all THAT hard to understand - just harder than it needs to be.
In short, this is a very welcome collection and it belongs on the shelf of any 20th century theorists or musicologist. You'll enjoy it.