Will you be looking at possibly joining the group of software products (Nisus Writer Express, OmniOutliner, and Stone Create) and integrating into your software a technology called Linback (http://www.linkbackproject.org/)? It seems to me that it would be a good fit for Bookends. As with everything I am sure that it would not be as easy as it would seem to a casual observer, but it maybe worth the trouble.
Yes, I'll be looking at that. At the moment it looks like LinkBack is intended for Cocoa apps, and Bookends is Carbon, so I don't know if it would work or not. I'm also interesting in seeing if it will be adopted by any word processor other than NWE...