WoW’s major content patch history

Highlights of all the major content patch releases by Blizzard for World of Warcraft between November 2004 and March 2011:

Original WoW release:

• 1.1: (nov. 2004) Release bug fixes
• Patch 1.2: (Dec. 2004) 5-man dungeon (maraudon), outdoor PvP area, holidy content
• Patch 1.3: (March 2005) 5-man dungeon, outdoor raid bosses
• Patch 1.4: (April 2005) PvP honor system
• Patch 1.5: (June 2005) Two battlegrounds
• Patch 1.6: (July 2005) Raid dungeon (BWL), Darkmoon faire
• Patch 1.7: (September 2005): Raid dungeon (ZG), Battleground (AB)
• Patch 1.8: (October 2005): Outdoor PvE bosses, Revamped questing in Silithus
• Patch 1.9: (January 2006): Two raids (AQ20 & AQ 40)
• Patch 1.10: (March 2006): Weather effects & Teir 0.5 armor set quests
• Patch 1.11: (June 2006): Raid dungeon (Naxx)
• Patch 1.12: (August 2006): Cross-realm BGs

Average time between patches for Vanilla: 1+3+1+2+1+2+1+3+2+3+2 =

Burning Crusade release:
2.0: (December thru Feb 2007) Preparation & release of TBC
Patch 2.1: (May 2007) Raid dungeon (BT)
Patch 2.2: (Sept 2007) Voice chat
Patch 2.3: (November 2007) Raid dungeon (ZA), guild banks, Season 3 Arena
Patch 2.4: (March 2008) Raid dungeon (Sunwell), 5-man (MGT) & Isle of Quel’Danas daily quests

Average time between patches: for TBC 3+4+2+4

WotLK release:

3.0: (Oct thru december 2008) Preparation & release of WotLK
3.1: (April 2009): Raid dungeon (Ulduar), Argent Tournament daily quests
3.2: (August 2009): Raid Dungeon (ToC), 5-man (ToC), PvP battleground (Isle)
3.3: (December 2009): Icecrown Citadel

Average time between patches: 4+4+4
(no major content patches in 2010 between 3.3 and 4.0. There was a minor patch classified under 3.3.5 to release Ruby Sanctum).
Cataclysm Release:

• 4.0 (October 2010 to November 2010) Preparation & release of Cataclysm