The biggest tourist trap is the Mall of America hands down. It can get really really busy. If you plan on coming to MN during a holiday season like Christmas be ready to fight the crowds. It's a mess.
Canyons, lakes, mountains, and rubber band balls are things to see for their size, but not shopping malls. In my opinion, the Mall of America is over rated. Hit uptown or downtown Minneapolis for shopping. The picture to the left is of the Gavidae Shopping Center located downtown on Nicollet Mall. The creative use of color and fountains are invigorating and there are never unbearable crowds like the Mall of America has.