After the book is officially, done done, I think that this site should definitely have members announce it's completion in various appropriate sites such as RPG.net and other locals.
You know, let people know it's finished.
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That sounds like a good idea.
Can someone pop over to the Planescape forum at The Piazza and poke us when you have this (or any other) netbook done. We are a multi-campaign setting community. We don't have as many PS fans as you, but the crossover communities (who like PS and another setting) might pick up news there.
I would also suggest you advertise this in ENWorld's 3e forums as well as their Creature Catalog conversion forum