I was in Chicago a couple weeks ago and found myself constantly comparing it to Toronto and I have to sadly say that we have a way to go to equal Chicago..
To be honest outside of the downtown I would rate Toronto higher than Chicago, but the downtown, waterfront, architecture, planning, transportation, etc, and even history of Chicago hits it out of the park compared to T.O..
If we actually treated our Waterfront and had a mayor that cares about the city again, we could get close, but too much damage has been done to many parts (like the central waterfront) to recover from it seems.
It seemed like Chicago had a huge head start on Toronto in terms of development and history, even though the two cities were started around the same time. Chicago just grew a lot faster it seemed, and that's a reason why they have so much beautiful, tall, dense old architecture and a great downtown compared to Toronto, as well as a much more interesting history.. (Show me Toronto's Al Capone and John Dillinger if you disagree)