For the 0.5.x release:
----------------------
ENTER changes char of TEXT under cursor
Retain color mode added to defc toggle
Quickly switch to adjacent board
Quick key for quick key reference (and mention on panel)
Tile under cursor displays w/ different for/back-color always
Exploit ability of board to "link to self" using index FF
Add monitor & blink rays to terrain documentation
Respond to exit event from SDL
Option: shift+arrow draws like tab
Number boards in the board selector
Char dialog: Alpha keys select characters 
File dialog: Alpha keys move the cursor

For the 0.6 release:
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Undo
ANSI file support (as much as ZZT can do)
Multiple backbuffers and toolkit file format
Object library sidebar menu

For the 0.7 release:
--------------------
Configurable keybindings
Configuration file

If Ever:
--------
Skins -- possibly using zzt file format as base
F4 textwrapping
Font editor
Scripting
ZZT-OOP shortcut keys
