Originally Posted by
biomieg
I'm not sure if the price will drop - my guess is that most of the people who buy proofs (either pre- or post-publication of the trade edition) do so because they are proof collectors. I can't imagine many regular fans paying hundreds of dollars so they can read the book a month before publication.
Proof prices are very volatile anyway because the market is small and the price is greatly affected not only by scarcity, but IMO also by the publisher (Scribner proofs are a lot more desirable than CD ones for example, at least to me), and other factors such as how well-loved the book is (proofs of the 'classics' are expensive). So it's hard to predict what will happen.