Tomorrow, September 23rd, Bungie is going to release Auto Update 2 for Halo 3. The major changes for players will be some new achievements and a revised ranking system. More details after the jump.

Here’s the information straight from Bungie.net:

Here’s a look at these achievements which can be earned via the Legendary Maps and Halo 3 Campaign: Vidmaster Challenge: Lightswitch (0 points) – Get to the rank of Lieutenant in any playlist in the new EXP progression system, Vidmaster Challenge: 7 on 7 (0 points) – Enter into any ranked or social playlist with 7 EXP on the 7th of the month, Vidmaster Challenge: Annual (0 points) – After 9/25/08, complete Halo on 4-player Legendary LIVE co-op, with Iron, and everyone in Ghosts, Double Double (25 points) – On a Legendary map, get two Double Kills during any ranked or social match, Poor Yorick (25 points) – On a Legendary map, get 3 Oddball melee kills during any ranked or social match, Came…From…Behind (50 points) – On a Legendary map, get 3 assassinations during any ranked or social match, Defend This (50 points) – On a Legendary map, get a flag melee kill during any ranked or social match, Flag Dropped (25 points) – On a Legendary map, get 2 flag carrier kills during any ranked or social match, Road Rage (25 points) – On a Legendary map, get 5 Warthog chaingun kills during any ranked or social match, Look Both Ways (50 points) – On a Legendary map, get a Splatter Spree during any ranked or social match.

Playlist Changes: Playlist Ratings are the playlist-level decoupling of Trueskill values (the in-game number next to your name) from Experience (the icon next to your name). You will now have a separate military rating (based purely on EXP) in each playlist. When TU2 goes live, everyone will begin at 0 EXP. This means that being a General in a Playlist is based on how many games you