I looked on the wiki, and it said that Graham Nardone, who I assume works for EA, said that it is loosely based on Pittsburgh. So there you have it.
Every time I played a game in Bridgeport, Kai Leiko moved out of Lola Belle's house the first or second sim day. Then one day, maybe a year ago, I saw him and Lola being romantic with each other, so I did some checking, and found that while their relationship with each other was very high, Kai and Lola's live-in personal trainer, Moxie Logan, can't stand each other. So he was moving out because of Moxie. Ever since then, whenever I set up a new game in Bridgeport, I use NRaas SP to make sure that if anybody moves out it will be Moxie, not Kai.
One of my two current games is in Bridgeport. Lola and Kai became engaged within a sim week or two, but went for a few more weeks without getting married, though they had at least one baby together. Then I got a notification that they had broken up. So I checked their moodlets. Neither of them had the betrayed moodlet, but according to their map tags, thanks to NRaas tagger, I could see that they were both upset. It seems they may have had a bad argument. I was disappointed, because I thought that for once they were actually going to get married. :'(