Huge hotel; great location; somewhat impersonal; best for business folks
This is a huge hotel with two towers. The location is simply excellent. You can walk to several attractions; lots of restaurants nearby; movie theaters, shopping not too far (under a mile).
I stayed in the renovated tower (I believe its the East side). Room was clean; I got a view of the river and the boats passing by, which was pleasant. 
I had requested a feather-free room during reservation. However, it took about 5 phone calls and six hours to get someone to change the sheets / pillows. It could be that they are understaffed. However, its not an excuse for such a time delay for a simple request.(especially from a loyal Elite member).
Its interesting that many reviews mention what a great job Nataly does at the Front Desk/ check-in. I vouch for that too. She was there during check-in and check-out. and she does do a great job. Explaining everything with a smile.
Otherwise, I found this hotel very impersonal. There was just no sense of belonging. You are just another visitor..thats about it. 
One unusual thing I noted is that this hotel does not provide Shower / Bath Gel...which is incredible, considering it is the prime Hyatt Regency in Chicago.!
However, it served the purpose for me for the time I spent. (except for a six hour wait to change sheets/pillows).