But my question is this: who says PvP matters in the first place. Look at the two MMOs this year that trumpeted their PvP: Vanguard and Fury. They're suffering, and it's not just because they couldn't provide a great PvP experience-- it's because they couldn't provide a great experience overall. PvP isn't the only thing WAR (or any other MMO trying to become top dog) will have to do right to succeed-- what it'll have to do is make sure that there's a core gameplay experience there (be it PvE or PvP) that will push people to stay with the game. Endgame PvP means nothing if no one wants to play enough to get that far.
Now, Warhammer does look like it has some excellent incentive to play-- even if the core gameplay suffers, players may fight through it just to see the RvR stuff (and if the Warhammer devs are smart and talented enough to make RvR the core gameplay, all the better). But it's not just about comparing one game's PvP to another-- the way a game becomes popular is that the core gameplay itself (whatever it consists of) stands on its own.