"Sad news for Halo 3 fanboys this weekend. The longstanding tradition of the Double EXP Weekend is on sabbatical this week. Don't worry though, it will be back, stronger than ever very soon. The reason for the missing double EXP only leads to more sadness though. You see, the intended playlist was part of the upcoming Halo 3 update. That would be fine, except the update has been delayed until next Tuesday, so the Double EXP Weekend had to be delayed with it.
At least we have a solid date for the update now. The update is set to contain all kinds of changes, including a new Social Team DLC playlist, Legendary-required Rumble Pit and Social Big Team Battle. Other changes are also planned. We expect we'll hear more by next Tuesday."