Yes, it's true. Of course you'll need to run Bootcamp with a copy of Windows XP, but with Apple's recently announced switchover to improved nVidia graphics cards in their laptops, the possibility of running your favorite MMO on an Apple laptop is here.
In an article over at Obsessable, they just had to try it for themselves. Not only did they get Warhammer Online to play on the newest MacBook, but they got it to play well. They report, "In person, there was no pixelation during game play, just a few jittery moments when I had the texture mapping graphics set to their highest and most detailed. These were very few and far between, however." Check out the two videos documenting their experiments with WAR on a MacBook after the cut.