The browser route is something i plan to explore, but i'm waiting to see if add-ons for the N900 Maemo Browser become available. I don't really need the majority of what Sword provides, and not having to deal with their modules and code make the whole project much less heavy.

My Zim notes:

DOM-modification
• MicroB for OS2008 supported Greasemonkey addon
• http://shiftspace.org scripts do highlighting and annotations as well as providing a centralized server for storage and a sharing mechanism

Some custom hacked-down version of the shitfspace project combined with a simple downloader/packager for the texts could provide a very nice reading experience right within the browser.