The iLiad I have in front of me has not got a cover and there is no sign on the casing of any provision to fit one, I suspect that it will simply be provided with a slip in pocket type case.
Yes .txt and .html content can be added, content stored on the iLIad is divided into four categories - News, Books, Docs, and Notes, and from what I can understand of the system (no documentation yet) it seems that these are simply the equivalent of folders in the iLiad's file management system. They can be accessed by pressing the appropriate key at the bottom of the display. Although I have yet to see the PC based download software I would assume from what I have been told that it will simply be a matter of placing the pocument into the appropraite file folder.
The writing function is not yet implemented on this machine, but I am informed that the you will be able to easily input hand written annotations, drawings, even shopping lists. These can then be transferred to a connevted PC. I asked about the image format for the handwritten input and answer I was given was simply that it would not by either JPEG or GIF.
The iLiad does not yet have any contents like calenders or address books, but I am sure that these will be added in the very near future since they are essentially just publications.