Timeline suggestions.

There are some errors in the timeline:
World Boss release
Patch 1.3.0
World bosses were released at the same time than dire maul.
PvP Honor System release
Patch 1.4.0
PvP Honor System was released one month after Dire Maul.
Battlegrounds release
Patch 1.5.0
One month after the honor system release.
Patch 1.7.0
Three month after the honor system release.
World Boss release
Kazzak and Azuregos will be available once Onyxia's head will be on a spike.
Dire Maul will open 1 month after Molten Core & Onyxia Lair content is cleared.
Patch 1.3.0
Diremaul
Diremaul, a new dungeon for players level 56-60, is now open and ready for business. Diremaul is populated by a fierce tribe of ogres and is located in the western region of Feralas. Diremaul will be limited groups of no more than five players each.
New Outdoor Raid Bosses
Two new outdoor raid bosses have been introduced to Azeroth. Azuregos, a monstrous blue dragon, has landed in Azshara, while Lord Kazzak the demon can be found in the Tainted Scar of the Blasted Lands.
World bosses were released at the same time than dire maul.
PvP Honor System release
Patch 1.4.0
PvP Honor System was released one month after Dire Maul.
Battlegrounds release
Patch 1.5.0
One month after the honor system release.
Battlegrounds arrive!
The Warsong Gulch and Alterac Valley battlegrounds are now available. The Warsong Gulch entrances may be found in the northern Barrens near the Mor'Shan Rampart (Horde) and south of Silverwing Outpost in Ashenvale (Alliance). The Alterac Valley entrances may be found east of Sofera's Naze in Alterac (Horde), and in the Headlands of Alterac (Alliance).
Patch 1.7.0
Three month after the honor system release.
Arathi Basin
Join the League of Arathor or the Forsaken Defilers as they battle for the precious resources stockpiled within the latest Battleground, Arathi Basin! Pitting 15 members of each faction against each other, the race is on to be the first to 2000 resources, capturing strategic landmarks around the Basin to increase your team's gain and cripple the enemy. With an all-new set of reputation-based rewards, there's never been a better time to join the war!