I've already had two friends ask me what today's news will do to values for Salinger material. Books, even rare first editions, will probably not appreciate considerably more than usual. For signed items, it's difficult to pin down exactly, but the short answer is that they're going up. Salinger is a notoriously hard autograph to get. Letters, manuscripts, and even clipped signatures demand a high premium in the market, and after today, and in my opinion, prices will spike for awhile and settle in at a higher plateau that they're at now. How much higher? Who's to say?
I think part of all of us who call ourselves Salinger fans hoped that one day he would snap out of his self-imposed isolation and re-enter the world, as if he had been under a magic spell since the early 1970s. Then, maybe, JUST maybe, we could have a letter returned or a book signed.
Rest in peace, Jerome. We will miss you. Most of all, a lot of us will miss that we missed you, and that we never got to see or meet or interact with you at all, for Chrissake!