Yeah, there was a big thread on it back when it happened. I'm pretty sure that Mall of America decided to pull it on its own though. They got a full refund after it had been running for 3 days or so. 3 days of free advertising ain't bad.
Mall of America said it was "too political", and that's the reason they gave for pulling it. I can see that, because it's a little more than just a mall... It's a tourist draw, kind of like Disney World. They want it to be all happy and fun so people will buy things, have a good time, then tell their friends about it. On top of that, it's privately owned, so I respect their property rights to pull the ad as long as it's allowed by the contract.