Aided Vol'jin's troll uprising during Patch 5.3: Escalation.
Rewards Title: Darkspear Revolutionary <Name>
The title "Darkspear Revolutionary" is not shared among characters on the player's account. Players will have to acquire the achievement on each individual character. Also - and this is important - the achievement and title are only available during Patch 5.3! Afterwards, it will become a Feat of Strength unobtainable by any additional characters.
The Alliance equivalent is Hordebreaker.