This is an extremely popular outlet mall that attracts thousands of visitors every year. However, in my opinion, it's poorly designed, filled with low-quality/over-priced merchandise, and lacking a common sense floor plan. Don't come here on a weekend unless you're happy to walk slowly in a sea of tourists and scrounge for a bargain among the rubbish. Also, the Rainforest Cafe here used to be quite good, but the food was very mediocre the last time I was here (still a cool place to look at, though). A better bet is the Chili's restaurant (a good medium-priced chain) just across the street from the mall, or any of the other restaurants nearby. Also, I'd stay away from the food courts in the mall itself--not long ago, they shut down a whole section of one of them after someone found a roach in his sandwich. (yech!!)
Unique Suggestions: If you are a shopaholic and feel that you must see this place, have a look at their website first and organize your game plan. :) http://www.gurneemillsmall.com
Fun Alternatives: There are plenty of nice shopping opportunities in the strip malls nearby! These include: Best Buy, Linens 'n Things, Borders Books and Music, Cost Plus World Market, Old Navy, a big Hallmark, Bath and Body Works, and plenty of grocery stores.
Six Flags Great America-Fun time, but bring lots of cash! Major Tourist Trap!