"Wrath-Logo-Small/Cataclysm-Logo-Small Patch 4.0.1 (12-Oct-2010):
Removed miss chance of this effect. (Untested, based off testing on Growl and Dark Command)
Wrath-Logo-Small Patch 3.0.8 (2009-01-20): Range increased to 30 yards, from 20 yards.
Bc icon/Wrath-Logo-Small Patch 3.0.2 (14-Oct-2008): Range increased to 20 yards, from 5 yards. Cooldown reduced to 8 sec.
Bc icon Patch 2.3.0 (13-Nov-2007): The chance for this ability to land successfully on its target is now increased by hit rating. However, Taunt remained classified as a spell for the purposes of determining miss rate versus mobs. That means that against a mob 3 levels higher than the player, Taunt has a base chance of 17% to be resisted (a miss).[citation needed]
Vanilla WoW: on release, Taunt did not create extra aggro for the warrior, it only forced the mob to attack the warrior for 3 seconds."