I've been thinking about a much more general idea recently: basically twitter, but for data (in JSON format), not just text.

A company could simply announce all new publications, and you could subscribe to that stream, filtering for paperback (and possibly authors you are interested in).

Of course, there are hundreds of alternative use cases.

(Interested in doing the project with me? drop me an email moritz@faui2k3.org).

Luzme.com does similar for ebooks (audiobooks and deadtree books coming soon). Shows availability and prices for ebooks across all major stores in 8 countries; use your existing watch list at Amazon, Goodreads, LibraryThing or setup a new one and we'll email you price drop alerts; register an interest in an author and we'll tell you when they release a new book.

I guess the question is how big of a market is there for this service? You could have alerts for Kindle version, audiobook and/or paperback. The monetization would be simple through Amazon affiliates, and implementation could just scan Amazon periodically.

I think http://luzme.com/ can do this? Not sure if it's E-book only tho

i am often interested to find out when kindle version is available. amazon should implement this.