The downtown shopping mall is another of those bright ideas from the urban-renewal era that didn't turn out so well. Take Philadelphia's own Gallery at Market East. When it opened 37 years ago, it was hailed as a miracle cure for that fading shopping street. Today, poor East Market Street is holding on by its fingernails, and it's the Gallery that now needs reviving.

Maybe that explains the excitement over last week's news that a high-end clothing discounter out of New York was setting up shop in the old Strawbridge & Clothier. While the store, Century 21, will occupy just a small portion of that art deco building at the Gallery's east end, we're told it will attract a species that hasn't been seen much of late on Market Street: the middle-class shopper.

Because it is the nature of Philadelphians to bemoan their problems as both unique to the city and worse than elsewhere, it's become common to hear the Gallery's condition described in apocalyptic terms. The mall is said to be a dying white elephant, more blight than boon, dangerous even, because its customers come from less affluent quarters.

It is true the Gallery has seen better days, but it's wrong to think of it as a failure. It might help put things in perspective to know that Columbus, Ohio's City Center - a sister mall built by the same developer - did so badly it was razed after 20 years. In contrast, the Gallery's concourse is routinely awash with shoppers. It has survived, in large measure, because it's a major transit hub that offers shopping to people from retail-starved neighborhoods.

The big reason it's seen as a disaster is its architecture by Bower & Fradley (predecessor to BLT Architects). With long, blank, windowless walls on Market and Filbert Streets, the Gallery repels pedestrians.

The fortress look is made worse by the cordon of parking garages, the poor interior lighting, the sameness of the shops, and the high vacancy rate on the upper two levels. Strawbridge's closing in 2006 greatly added to the gloom. And in an economy where suburban malls get face-lifts every decade, it's hard to believe there are sections of the Gallery that still retain their original, earth-tone floor tiles and other '70s details.

Yet, for everything wrong with the design, the Gallery still pulses with life. On the concourse level near the train station, the place has a town-square vibe that would have warmed Jane Jacobs' heart. You can't help but notice what she called the "ballet of the good city sidewalk" - people greeting acquaintances, seniors hunched over chessboards in the food court, teenagers flirting with schoolmates.

The Gallery isn't so much a mall as a climate-controlled city neighborhood. Tevin Patterson, 20, a Rutgers-Camden student who sells photo portraits near the Ninth Street entrance, says he can hardly go a few minutes without being fist-bumped by someone he knows. His godmother works at the Net clothing store. A high school friend is one of the security guards. He met his girlfriend at the mall.

Growing up in a dicey part of Grays Ferry, Patterson saw the mall as a safe place to hang out. "The Gallery was the first place my mother let me go on my own. I'd come after school with friends," he told me. "The Gallery is great. Who doesn't like the Gallery?"

Plenty of people, including the company that now owns the mall, the Pennsylvania Real Estate Investment Trust. By traditional measures, the Gallery underperforms. It racks up $359 in sales per square foot, compared with $623 at the company's upscale Cherry Hill Mall. With 1.5 million square feet for retail, it's way bigger than today's urban malls - a major problem, says CEO Joseph Coradino.

At some point, the Gallery stopped being seen in Philadelphia as a place for everyone. It has trouble getting tourists, conventioneers, and commuters inside - not to mention that swelling cohort of affluent residents living in Center City. Century 21 is an inspired choice for a new anchor because it appeals to both high and low. It can be the gateway that persuades the middle class to shop the Gallery again.

That's not a new goal, notes Max Page, an architecture and history professor at the University of Massachusetts. When downtown malls were first adopted as an urban-renewal strategy, "it was, 'How do we bring the middle class in from the suburbs?' Now they want to appeal to the same class, but living nearby," he explains.

In an ideal world, everyone in Philadelphia would shop at the Gallery. In Los Angeles, the Grove draws from all neighborhoods. But to make that happen at the Gallery, a top-to-bottom renovation is necessary.

Though Coradino keeps his long-range intentions close to his vest, he did reveal some plans. A firm that specializes in mall renovations, JPRA Architects, has been retained. The main goal is to break through the blank facade walls within three years.

Now that Kmart has left its big box at 10th Street, Coradino wants to insert an atrium into the center of the space and surround it with smaller, street-facing stores that could house restaurants and bring energy to Market Street. It's been rumored that Eataly, the luxury Italian grocery, is destined for Strawbridge's old food hall, next to Century 21. Coradino would say only the Philadelphia market is big enough for both DiBruno's and Eataly. He also promised "surprises" for the Gallery's nearly empty top level (where The  Inquirer's parent, Interstate General Media, is located).

The project will play out as a series of chess moves. Market Street is clearly in flux, with proposals to build apartment towers on the sites of two former department stores, Lits and Snellenburg's. Meanwhile, a casino could end up on another department-store site, Gimbel's old home on Eighth Street.

Dowdy as the Gallery is, it has lots of potential, including a great location and a growing downtown. "We don't need different customers," insists Coradino. "We need more customers."

One way to attract them is to make sure the Gallery functions as a big tent for the whole city, a large, lively neighborhood hangout in Philadelphia.