i found a link on the B.net blog page Enjoy!!! IGN: Halo 3 Mythic Map Pack Interview Halo 3 Mythic Map Pack: exclusive Bungie interview | T3 magazine online They both show a Very important component being added to Forge: OPTIONABLE GRID LINES!!!!!111!!1!!1!11!one!!111shiftone! Anyone wanna discuss the possibilities of this in Forge?!
Thats not all lol. There is the 'kill ball' which kills you if you enter the area it emcompasses as well as colored base markers and new filters.
You should post anything like this in the official Sandbox thread, to many of these things were being created.