This is my opinion for best in class PvP-ers for Alliance and Horde respectively.
I should note that this list is based on the observation period of last 4-6 months.
Also it is based only on performance in Warsong Gulch.
The list is construed through skill, tactical acumen, efficiency, gear and general demeanor.
Alliance / Horde
Mages: Gnomuch / Heavenwaits
Gnomuch is the greatest WoW player that has ever lived. Heavenwaits is unbelievably useful and elusive even when brought down to a fraction of his HP.
(honorable mentions to Falladan, Elsa and Bettyrubble; *edit - and Danielle but haven't seen him online much)
Warlocks: Bazzaroth / Justcurse
Bazzaroth has probably the best movement skills in game.
(honorable mention to Zenedar. One one, Zenedar may even be better than Justcurse, but Justcurse is tactically more disciplined. Zenedar will sometimes engage in personal duels, disregarding the flow of the game.)
Shamans: Kelorn
When all is said and done, the best shaman.
Paladins: Renovatio
True game changer who can fill any roll in BG. Smart and calm.
(honorable mention to Sansasyon)
Hunters: Boshko / Selenchen
Boshko is calm, concentrated and generally nice to everyone, while at the same time never loosing heart or giving up. Xelenchen / Selenchen is dominant in what he does.
(honorable mention to Xelenchen, but this is an alt of Selenchen, so Boshko has the advantage. Also honorable mentions to Khrey and Saeldaria).
Warriors: Rectal / Irakan
Even with minimal help, Rectal is an unstoppable force. He does not give up, does not relent, and handles hard situations like a dwarf warrior.
(honorable mention to Xyhpa. Advantage to Rectal because of his ability to locate and decimate FC, while Xyhpa is the best warrior tank FC. Honorable mention to Krewlz as well, but Irakan got the advantage due to longer survivability. Also a honorable mention to Dawayne).
Rogues: Ghostto / Anarchii
(honorable mention to Bisey, but advantage to Ghostto because Bisey hasn't been online that much. Honorable mention to Mirando).
Druids: Icefoxy / Mamooko
Mamooko is by far the best at what he does. He is disciplined and does not get taunted to go off script but rather concentrates on FC-ing.
(honorable mention to Umbridge and Tattiva)
Priests : Chou and Labyssa / Nenemae and Bpositive
Chou is the best healer. Labyssa is often disputed by other players, but Labyssa has 57202 confirmed kills and the rank of Marshal in Victoria's Secret gear. One wonders, what would she be in full T3 - Azshara?
Nenemae is a very strong healer with a lot of sustain. Bpositive is tacticaly very sound.
(honorable mention to Remik, who is just too suicidal)
This is all of course my personal opinion, and we are discussing here only "the single best". There are much and more great players on both sides in wsg, and each of them would not be out of place if put on this list.
