Bungie Teases Halo 3's Future

Could a full map editor be on its way to Halo?

After teasing a new game and hinting that there will be major changes to Halo 3 on it's community site on bungie.net.

In this video Bungie talks about working on a new project and then ends with the line "Wait a second, there is no way we're showing this yet." The video then zooms out to be what appears to be a full map editor. Is this what is on it's way to Halo 3?

Watch the video for yourself.