A rocky start to a disappointing stay
I had a 4 night stay in August 2012, traveling with my small dog and family members. Upon check-in I was informed that my reservation had been for check-in the previous night and was charged for a missed night's stay. Apparently the hotel did not have a record of my changed reservation which had been modified 2 weeks prior, so I had to spend 15 minutes digging up my travel service's confirmation email to show that I had changed the reservation and finally it was taken off my bill. I don't know why the hotel wouldn't have called the prior day to confirm if I was arriving but instead just charged me for it. In any event, this set the tone for my 4-night stay. 
I was taken to the executive king suite room (city view) and found what appeared to be rust marks all over the floor near the furniture. It looked as though the carpets had been cleaned without putting any protective padding under the furniture which then rusted. I was switched to a new room which was fine but had dust on the tables and stains on the nightstand from what appeared to be a soda spill. Someone then delivered the "pet amenities" which consisted only of a dog bed. I requested a food and water bowl, and this took another 30 minutes to be delivered. Of course each time there was the expectation for a tip (a stark contrast to my previous stay at the Waldorf where there is a no tipping policy - heavenly!) 
The housekeeping was very inconsistent -- some times turndown service was impeccable with a fresh bottle of water and my slippers laid neatly by the bed, other times my slippers would be scattered somewhere and no water bottle in sight. We had to call for towels on one occasion. Another time, we left to go to shoppping and returned 2 hours later to find housekeeping in the room; we asked for privacy for an hour to eat lunch and change clothes and for them to return. They never did and so we had to call again to have them clean and do turndown and had to wait it out in the lobby. They were very thoughtful to leave a plush toy with a gift card after I mentioned that my brother had a baby at nearby Northwestern, but overall the service was very uneven. We often heard housekeeping staff talking loudly out in the hallway as well - there just wasn't a general sense of discretion that I usually notice at 5-star hotels.
The hotel decor was apparently recently refreshed but the bedside tables looked to be straight out of the 1960s and the marble bathroom was very boring. The bathroom amenities were very skimpy - I had to call housekeeping for mouthwash and a razor, something that I would expect to find provided in a 5-star hotel without needing to request. The rooms have free wi-fi but it is slow as molasses. High-speed wi-fi comes at a price (I believe $11.95).
Finally, for those traveling with pets, please note that the hotel restaurant will not serve coffee or any food to the lobby so the only option for eating with a pet in the hotel is ordering room service. Stark contrast to Kimpton hotels and even the Ritz where they will accommodate a dog owner by discreetly serving off the menu in the lobby.
Overall, the location is unbeatable, but the service needs some improvement and there is room for improvement for accommodating those traveling with pets, although kudos to the Four Seasons for not having a pet fee for dogs under 15 lbs. I have enjoyed much better service and nicer accommodations in other Chicago luxury hotels (the Waldorf being number 1) and other Four Seasons locations. I likely will not be staying at this location again.