App Update!
The app has been updated, adding features such as Highlighting and Notes. You can also Copy small pieces of text (and paste into a Note, or into another app) and look up Definitions in a dictionary.
In order to make these features work, the books themselves have had to be modified slightly, so you will need to run Restore All (in the Bookstore) once you have updated your app. That will upload all the books you have purchased.