Personally? You know what the true lesson here is?
Warhammer should have had it all. It should have been the gritty, alternative universe to WoW's disney-fied theme park. So what exactly led to warhammer's demise?
The game had many genuinely good ideas, ideas that were adapted into future MMO's past it. It was supposed to have far superior PvP content vs WoW's. Didn't it support realm vs realm combat too? All these things should have led up to a game which should have given WoW a good run for it's money.
And then Wrath of the Lich King came out and buried WAR. I think this game deserves a developer post-mortem. What exactly went wrong?