The editor is something that I, personally, would love to see in the SDK as I'm sure a lot of the other guys and gals at Volition would. The problem there is the super-tight interweaving of the editor in with our version control system and many other internal-only systems. It would take a massive amount of work and a lot of novel solutions to get it ready to go out of the door. I don't see a way for that to happen without Koch and Volition getting behind modding in a paying way. Right now we do this on the side in our personal time out of love for the game and the fans, but something that large just wouldn't make it out in a reasonable amount of time in that manner.