Some interesting developments regarding the
OpenReader open standard: OpenReader is in discussion with OSoft to develop a working OpenReader model using OpenReader's standards and OSoft's
ThoutReader framework. ThoutReader is currently Java-based and doesn't run on PDAs. But they've plans for cross-platform support by switching from Java to Perl or Python (although I am not convinced that any of these two languages would be any better for mobile devices).
More over at
Teleread.