Philadelphians occasionally refer to their city -- somewhat deprecatingly -- as the "sixth borough" of New York, and with almost 8,000 commuters making the 75-minute train ride between the cities each weekday, the label seems not far off the mark. But Mr. Kreslins and Ms. Gaeta are a new breed of Philadelphia-bound commuters, those who come from New York by train or the popular Chinatown bus for a weekend and then come back, with a U-Haul, to stay.

They are the first wave of what could be called Philadelphia's Brooklynization.

Hard numbers assessing exactly how many new residents are from New York are not available, but real estate brokers are noting an influx of prospective buyers and renters from the city; club owners and restaurant employees have spotted newcomers, on both sides of the bar; and "everyone knows someone who's moved here from New York," said Paul Levy, the executive director of the Center City District, a business improvement group, and himself a former Brooklyn resident.

Attracted by a thriving arts and music scene here and a cost of living that is 37 percent lower than New York's, according to city figures, a significant number of youngish artists, musicians, restaurateurs and designers are leaving New York City and heading down the turnpike for the same reasons they once moved to Brooklyn from Manhattan.

"We got priced out of Manhattan, and we moved to Brooklyn," said John Schmersal, 32, of the three-member band Enon; two of them migrated here in January. "Then we got priced out of Brooklyn. Now we're in Philadelphia."

On a recent Friday night Mr. Schmersal and his girlfriend, Toko Yasuda, were huddled at the bar at the Khyber, a smoky rock institution in the nightclub-heavy Old City neighborhood, a Colonial area of narrow streets bordering the Delaware River east of City Hall, to see Love as Laughter, a New York City band. "We like going to shows here," Mr. Schmersal said. "In New York there are so many people, it's impossible to even get in to see hot bands."