Gilae
It has been my experience (albeit somewhat limited) that horde players on pvp servers tend to win in BG.
In an equally geared battle, Horde have a slight advantage due to certain racial abilities.
When said Horde are geared with rank 8+ PVP gear (or in the case of AD's A-teams, 11+) against people with greens or standard UBRS/Strat/Scholo raid blues, it's a slaughter.
I found this on the Official WoW forums:
Racials, defense...
Lets see here.
AV
1) Horde has more guards then Alliance.
2) Horde's guards respawn faster.
3)Their defense structures have more guards in them.
4)Their defense structures are harder to get to the flag.
5)One of our Alliance towers is useless.
6)Another Alliance tower can be ninja'd without any guard agro.
7)Horde have a skinnier choke point, 3 actually, one at the very begining it's very tight, another at the next building you get to with tons of guards basicly a small doorway also tight entrance, then another tight entrance directly at their two towers.
8)Horde's base is more like a maze.
9)Alliance base is wide open.
10) Horde can pincer Stonehearth.
11)Horde's first GY, only has one spot you cannot pincer it, they fixed that, along with horde's obvious advantage of an extra graveyard which they later on made neutral.
12) Our armor turn in NPC doesn't respawn and is non elite, I forget if they fixed this or not.While horde's definately is respawns, forget I think elite aswell.
13) Their outpost (The giant building thing with a leutenant in it that gives the buffs) is stronger then ours. (Ours is a crappy caster that is easly beaten while horde's is a warrior like NPC that hurts alot more, fear AoEs, and whirlwinds.)
14) Horde racial's are better, WoTF dispelling fear and charm effects, AoE stun, stun resist rogues can't stunlock those orcs, troll doesn't count might be better in 1.9 though!While Alliance is, a "out of immobilize" ability but requires a 1.5 cast time which makes it useless, doesn't work for freeze trap either, Shadowmeld that if we move or do anything basicly it cancels it useless unless you're a hunter at a spot YOU KNOW someone is going to come by, dwarf racial only useful for rogues to get rid of bleed to be able to vanish but with all the AoEs useless anyways.
15) Shaman can do alot more useful things than paladins in AV.
Now lets see what Alliance has going for them in AV.
1)Can jump over fence to get into their base, nope they fixed that.
2) Can pincer their first GY, nope they fixed that.
3) Can cap flag at TOP of tower just outside the tower's back of their little hut but they still agro you usually.
That's pretty much it..
WSG
Horde -
1) Ghost wolf in level 20-29 bracket and above, before druids get their travel mount making horde only viable runner in that bracket.
2) Shaman can snare entire raids in the tunnels and base, it lasts even after the totem is destroyed.
3) Racials again.
4) Alot better hiding places near horde base than Alliance base, I have horde characters I know so.
Might be more but I think that's it.
Alliance-
1) Shadowmeld for hunters only it benifits.
2) Paladin can bless of freedom on flag runner, but shaman will purge and make it useless.So not really.
3) Did they fix the MC bless of protection thing that made their horde drop Alliance's flag?
That's about it.
AB
Horde-
1)Can access Blacksmith faster, proven this with just both teams running on foot towards flag.
2) Racials again.
3) Shaman bring more versatlity than Paladins.
Alliance-
1) Again shadowmeld only benifiting 1 clasls, hunter, while horde benifits all theirs classes and 3/4 of their races, maybe 4/4 once 1.9.So Alliance are outdone by this.
2) Bubble capping, been fixed though.
That's about it.
Other facts -
1) More alliance usually making Alliance more unorganized but even when they are organized horde can still usually win because their blant advantages.
2) Alliance racials suck, I'd gladly trade shadowmeld for any of the horde racials, including Beserking once 1.9 comes out as it makes it actually useful as shadowmeld sucks except for hunters.
3) 4 hour BG experience, our raid was organized was winning we were at their main base, horde tagged Stonehearth, hardly any horde was left at their base while we were all at their main last base.Eventually because of their advantage for guard respawns defenses and more numbers for guards, they delayed us long enough for horde to cap SH and get to our mainbase and win.While we had, Ram-riders, Ivus the forest lord, all the Gryphons out, while they had nothing, their blant advantage of defense structures, numbers of overwhelming zerg of guards (have screenshots), and respawn of them aswell has such a hard defense they delayed us for their raid to get to Dun baldor (sp?) and win the raid, I /AFK'd out after they capped SH.Other people in there said we lost, friends.
5) Shaman > Paladins in PvP, and pretty close to Paladin's PvE which makes overall Shaman > Paladin, also horde > alliance racials, which makes Horde overpowered.No balance.