@jlnr: Since it's basically an editor to "do whatever with GameObjects" (create, delete, rotate, fade in/out, resize, move, clone) you could most likely use it for many types of games. Made a quick crappy vid of me editing a sidescroller game with chingus viewport-trait:
http://ippa.se/videos/holiday_droid_edit.avi ... depending on your gamelogic you can switch back and forth, playing / editing at (almost) the same time. Basically starting the editor is just push_game_state(GameStates::Edit) from the state where you wanna muck around with the game objects.
@banister: Hah, I found a dude on some pixelforum who painted him... but then I got stuck on the circle vs rect thingie for 6 months :). Mailed him again yesterday, hoping he'll wanna draw more stuff now :).
All the vids I create with Camtasia gets this blueish overlay when I play it in VLC ... do everyone else get that too? >:O