I'm a new user, but here's a couple of features that would be extremely useful to me
1) this has been noted above somewhere, but the ability to remember login/passwords in the web browser like many web browsers (or perhaps support for a browser like Firefox mobile-Fennec).
2) the ability to recognize footnotes in .rtf, .doc and .docx formats. Currently, it doesn't even put in a number to let you know a footnote exists. I'm looking to use the Pocketbook for academic work and grading, and this would really make a big difference...currently I have to convert anything I receive into a pdf, which often isn't as user friendly to read (text size, layout, etc.)