Are there existing people in the city? At any rate obviously the world would tumble into extreme turmoil. The economies of all of our former cities would grind to a horrific halt without our $200k/yr jobs that ALL of us have. All other cities would experience a huge influx of ugly babies since we are ALL incredibly handsome individuals. Since we would be bringing our girlfriends or wives with us, who obviously MUST look better than Jessica Alba, Megan Fox, etc. since we consider those people to be hideous, beastly creatures, the females who currently live there would have to move down into the sewers lest we think they have some sort of disfiguring disease. Since we can ALL bench press 980 pounds, there would be unprecedented progress in any labor-intensive activities.
It goes without saying that we would all have immaculate resumes.
On the bad side, there would be enough firearms for the government to declare us the single greatest threat to stability in the united states, and we would have a huge collection of cages filled with police where we'd throw tomatoes at them and tell them how horrible they are as people on a daily basis.