The two games are based upon war torn fantasy realms, and both games allow you to choose between which sides you wish to be part of; the alliance and horde for world of Warcraft and the armies of order and destruction for Warhammer online age of reckoning.
In these factions you pick you can chose which character race you'd like to be in the factions. In WAR there are will only be 6 races three to each faction; the dwarfs, the empire, and the high elves on one side, and the green skins, dark elves, and chaos on the other side. For World of Warcraft there are as of now ten races splitting five to each side. On the alliance side there is the; the night elves, dawrfs, gnomes, humans, and the draenie. On the hordes side there are; orcs, trolls, tauren, undead, and the blood elves.
The difference in the two games aren't as noticeable on the surface as they are on the interior game side, though the look of the games does have their own signatures, there is a darker more realistic feel to WAR as to WOW toons. Beside two distinctive graphical styles, it's really the game play that troughs you in two different directions.
World of warcraft is very epic and adventure driven, making the adventure very full fantasy and making it easy for you to role play yourself into the character. Warhammer online has a more player vs. player, realm vs. realm feel, where in WOW you can do player vs. player for good items and a desire to show your friends on the other side who's better, it is still based on sub portion of epic. In WAR however an atmosphere of constant war, you can even level from beating other players. In WOW the rewards for player vs player are as said earlier a chance to receive epic gear. In WAR the best players at the end of the week will have temporary statues erected in their likeness.
The two games share a similar appearance and the games have similar origins, however as soon as you play the two in contrast to each other you find two distinct games. Making you the judge if one is better than the other. Warhammer Online also has its own unique game play known as Realm VS. Realm which was derived from their previous successful MMORPG known as Dark Age of Camelot. The opposing faction are able to compete in large fights in open battle and castle sieges of well over 200 players at the same time. Talking about processor overlord eh? In World of Warcraft, you are permitted in open field battle in player vs. player realms but is very limited due to vast restrictions and lack of rewards for fighting against the opposing faction.