Pretty Standard Hyatt Property
This Hyatt is located right downtown, on Wacker near Michigan Ave and the famous Miracle Mile. It's a great location if you are going to be spending lots of time in the central core of Chicago. 
This is a huge hotel, so be prepared for big crowds and lots of commotion. I believe the largest in the City of Chicago and it caters to groups and conferences.
My check-in was uneventful. The clerk was very friendly and helpful, getting me off to my room with no wait. At check out I tried to beat the line and use the kiosks. They weren't working, but a very nice chap at the counter cleared my account quickly.
The room is tastefully decorated in a standard business class hotel contemproary style. It looks like any recently renovated Hyatt, Sheraton, Hilton or Marriott. There was nothing remarkable about the rooms. Comfortable size. Air Conditioning worked very well. Water pressure and temperature were good. Room was clean. Bed was quite comfortable. No noticeable noise transmission from the hall or nearby rooms
Amenities are pretty pricey.....$52 a night for parking, $13 for marginal internet service, and mini bar prices through the roof. I was there 4 nights, however a morning newspaper only appears at my door on two mornings.
Their feature restaurant, Stetson Chop House was closed for renovation. Bistro 151 sits in the center of the main atrium and can be very noisey. Food is average at best and it's pricey. The price of the breakfast is crazy. There's a Starbucks stand in the main atrium that is open 24 hours a day.