
Blizzcon, the yearly Blizzard Entertainment convention, is an exercise in community building. At this year's opening ceremony, Mike Morhaim, Blizzard President and Co-Founder, lavished the predominantly World of Warcraft playing crowd with praise and fan service. A casual observer might see a strange festival of mutual love between developers and players. There is a concerted effort by Blizzard to incorporate their user base, particularly WoW players, into their corporate identity.
To some extent, Blizzcon is an attempt to foster a corporate/consumer culture around Blizzard software. Interestingly, its WoW playing fan base itself may be divided along cultural lines. The difference between Horde players and Alliance players, the two competing factions in the Warcraft universe, is palpable both in game and out.
One can hear the disparity between WoW players by climbing on stage and yelling each faction's battle cry. "For the Horde!" causes the crowd to rumble with applause. "For the Alliance!" results in a noticeably quieter applause mixed with the boos and jeers from Horde members. While I saw no outward hostility between players, maybe the sheer amount of horde emblems was enough to quiet most alliance members. From all outward appearances, the Horde populace has a stronger and more passionate culture than the alliance.
Like most cases of cultural antagonism, both sides have their share of stereotypes. To many Alliance players, Horde players are hostile, angry, ganking, immature elitists. To many Horde players, the Alliance are whiny, soft, ganking, immature elitists. The stereotypes wouldn't be all that different were it not for one thing. There is a large number of people who believe the game and its makers favor the Horde.
This has been a long standing debate, admittedly between a vocal minority of WoW players. The argument stems from a perceived imbalance between the two factions in PVP combat. Those attempting to support the claim frequently cite racial traits. Blood Elves, for example, have a particularly deadly mass silence. Cataclysm, the newest expansion, allows this race to play as Warriors, who are traditionally weak against spell casters. Likewise, Cataclysm will give the Goblin race to the Horde with a set of racial talents many consider far better than the Alliance's Worgen race. There is also a common assumption that most Blizzard employees play Horde. The fact Mike Morhaim himself plays for the Horde themed metal band, Level 80 Elite Tauren Chieftain, doesn't help this perception.

The likely explanation for the difference between the two factions is how they are perceived as distinct culture by players. More competitive players seem drawn to the Horde. This could be because of a history of PVP success or because the Horde's monstrous races appear more brutal and menacing than the Alliance races. Perhaps the stereotypical valor of "the good guys" attracts players who favor story telling over violence.

For smaller MMOs, a poorly managed play style divide can cripple its online community. Ideally, the developer should support both play styles regardless of faction. Perhaps Blizzard should support real world cooperation between factions or foster Alliance pride by creating an Alliance themed band.
Established cultures are amazingly resilient creations. Changes to game design must be the primary method by which developers sculpt culture. Blizzard's decision to include a more ferocious looking race in the Alliance and a diminutive race into the Horde is a deliberate attempt to attract different players to each faction. Unfortunately, any dramatic changes may weaken player loyalty to their faction and to the game's lore. It appears sculpting culture and identity is no easier in videogames than in real life.