For me, it was most interesting to see how much of the city that I'm familiar with today has been constructed in the time since this film was made. South of the river, basically nothing exists east of Michigan Avenue, and there's not much going on in River North either. Street cars still ran down the center of State Street, past the Marshall Field's building that was still occupied by it's namesake and not Macy's, as it is today. The Union Stockyard (as mentioned in the unofficial city theme song, "My Kind of Town,") was still considered a major landmark. The film also discusses the popularity of recreational fishing along the lakefront, showing crowds of men casting their rods from piers on Lake Michigan. Today, the idea of eating any fish you might catch in the lake yourself is virtually unfathomable.
Most striking, in my opinion, was how dirty all the buildings were. I'm not sure if that's a factor of people still burning coal for energy, more lax emission standards for automobiles, or just a more lackadaisical attitude towards facade maintenance in pre-Daley Chicago, but light-colored buildings like the Merchandise Mart are practically unrecognizable. Still, even if the city barely looks the same compared to 63 years ago, Chicago is every bit the ideal city to live and visit that it was all those years ago.