I was doing this for the other teams in my guild and thought I would share.
Most killed -> least killed.
H: Stone Guard (30%)
H: Feng the Accursed (26%)
H: Gara'jal the Spiritbinder (23%)
H: Elegon (19%)
H: Blade Lord Ta'yak (14%)
H: Four Kings 5555 (13%)
H: Wind Lord Mel'jarak (11%)
H: Garalon (9%)
H: Will of the Emperor (8%)
H: Imperial Vizier Zor'lok (5%)
H: Lei Shi (5%)
H: Amber-Shaper Un'sok (4%)
H: Grand Empress Shek'zeer(3%)
H: Protectors of the Endless (3%)
H: Tsulong (2%)
H: Sha of Fear(1%)
what % of guilds have killed x boss data from www.wowprogress.com