Personally my heart lies within the Horde. I've played both Alliance and Horde races and I like Horde better. Alliance is a really good faction too, they have nice races like Dwarves and Draenei. I love all the Horde races excluding Blood Elf, everyone and their grandma is a Blood Elf. My favorite race is Troll and my favorite class is Paladin. I love the goblin racial traits, they are awesome.
Many WoW players say they think Alliance players are far to immature.
Although the Alliance has worgens which are a really cool race,
worgens make excellent druids.
Alliance has more paladins, everyone know paladins are the best.
Alliance also has the advantage of having more people.
HORDE or ALLIANCE?