In no particular order:
+ vi-mode
+ GUI toolkit friendliness (done for tk)
+ point-and-mark?
+ user customization support (maybe even try to read $INPUTRC?)
+ in general, implement more readline functions (just a matter of 
  typing, for the most part)
+ a more incremental way of updating the screen.
+ unicode support
+ undo support
+ port to windows

+ reduce verbosity
+ tabs
+ look up delete in terminfo? tcsetattr(self.fd).cc[termios.VERASE]
+ mention license?

+ find a font.  maybe I can bundle andale mono?