As of March 25th the 3-map Heroic pack for Halo 3 will be free.
http://www.bungie.net/News/content.aspx?ty...s&cid=13399
Lets get it on!
Also, the new Legendary map pack will be launching April 15th with 3 more maps, including a remake of the Halo 1 classic "Sidewinder"