There are no markets in the US where you have 5 CHR/Pop stations competing. There may be certain parts of the market, or fringe areas where one can pick up a handful of CHR/Pop outlets, especially with a good radio tuner. For example, I'm in a part of Nashville where I can pick up local stations 107.5 The River, 102.5 The Party, and I-106. Additionally in my car I can also pick up Magic 98.5 out of Cookeville and Wuhu 107 out of Bowling Green. Keep in mind that you cannot pick up the Bowling Green and Cookeville CHRs in downtown Nashville, nor in major parts of the metro area. In fact, I-106 and 102.5 The Party both have signals that do not cover the entire market properly.
I realize that you live in a part of New Jersey which could be categorized as CHR heaven - there's a plethora of stations one can pick up from several markets that do CHR/Pop. If you live in the heavily populated areas of Jersey that is usually not the case - in the Newark area you can "only" pick up the New York CHRs. In suburban Philadelphia on the Jersey side one can only pick up Philly's CHRs. If you live in Atlantic City then the only CHR that properly covers the market properly is adult friendly 95.1 WAYV.
Is CHR/Pop on the rise? Yes! And that's a good thing. It's about time more markets got a second CHR/Pop outlet. It also means that markets that have long been deprived of it, such as Las Vegas, Bakersfield, Norfolk, Denver, or San Francisco now get have a CHR/Pop station or two of their own. The format is obviously very healthy, performing very well in the ratings, and generating good revenues.
There are several markets with 3 CHR/Pop stations - Reno, Salt Lake City, and Nashville. But if we're talking about 5 local CHR/Pop stations serving the same market you'd have to look outside the country at places like Sao Paolo in Brazil, Manilla in the Phillippines, Athens in Greece, Milan or Rome in Italy, Nicosia in Cyprus, Bucharest in Romania, Istanbul and Ankara in Turkey, and San Salvador in El Salvador. Those are among the only places on earth at this time where one can pick up at least 5 CHR/Pop stations, all targetted at the same market/city.