Amazing.

Invigorating.

Fantastic.

Neat.

So said people like Nicole Cross, who gathered yesterday at lunchtime in the Comcast Center lobby.

"My friends said I had to come and see the big TV screen. So I came for lunch downstairs. Now I'm here gawking at it like everyone else. Doesn't it make you feel like you're in Tokyo, or someplace bigger, more technologically savvy?" asked Cross, of South Philadelphia, as she gazed up at Philadelphia's newest attraction.

"It's neat," agreed her sideburned friend, Jacob Keen, who said he did not want to appear too blown away.

Comcast and the developers of its new headquarters, Liberty Property Trust, hoped to create Philadelphia's version of Rockefeller Center with the 56-story Comcast Center at 17th Street and JFK Boulevard. Perhaps they have nailed their goal, but in a surprising 21st-century way - a super-high-definition video wall in the open-to-the-public lobby.

Showing for less than three weeks, the video wall is attracting crowds daily to the Comcast Experience, which, despite its name, has nothing to do with TV or the company's history.

The specs on the wall are impressive: The screen is 83 feet long and 25 feet high, but that's not nearly the interesting part. Comcast calls it the world's largest four-millimeter LED screen. It's a pixel riot with 10 million of them, in a giant screen five times brighter than the latest high-def TV.

And it gets better: The content is nothing like you'll see on TV, movies or Comcast's own gazillion-channel lineup.

It's artsy vignettes - one of them showing people who seem to live in the wall. Every so often, a man or woman springs to life and scrambles up or down the wall, or does a Cirque du Soleil-like exercise, or climbs a ladder. "Pretty esoteric concept," says Brian L. Roberts, the chief executive officer.

There are images of the earth from outer space, fish, flowers, trees, and professional dancers doing the Mashed Potato. When it's not showing video, the wall blends into other parts of the building interior.

A company official said Comcast had been stunned by the fast reaction to the video wall and would begin showing 10- to 15-minute specials of the best of the Comcast Experience this weekend. The once-an-hour shows will start at 8 a.m. and run to 10 p.m. Saturday and Sunday and will continue every weekend.

D'Arcy Rudnay, a senior vice president, said she had no estimate on the numbers of wall-gawkers. Yesterday at lunch there were about 50 people in the lobby, many of them dressed informally and just staring up at the wall. The word cool was tossed around a lot. Some visitors wore badges from other companies. Rudnay said the crowds had grown since the building's June 6 opening.

Roberts said he would like the video wall to become part of the local culture, like the Christmas lights at the former Wanamaker's department store. He plans to join with a consumer-electronics company and open a "Comcast Store" in the building, and the video wall fits nicely with that plan, he said.

The quick popularity of the Comcast Experience shows the power of entertainment and technologic razzle-dazzle to draw people to a place. The same excitement and draw had been expected of the public space inside the Kimmel Center on South Broad Street, but most weekdays the soaring space enjoys nothing like the crowds at the Comcast Center.

The Comcast Center lobby is open to the public 24 hours a day, and the video wall plays most of the time, except for several hours at night.

"It's fantastic," said Beige Berryman, a city planner gripping an iced coffee. "I don't know what to say other than you have to see it to believe it." She said it was "invigorating to see people enjoy the city this way," she said.

"It's definitely worth the trip," said Larry Jones of Mount Holly, who was in Philadelphia on personal business and stopped by, "and not something you can explain to people. You have to experience it."

Cross said the video wall seemed more like "an art installation than a big ad. People wouldn't gawk at an ad."

JoAnn Garbin of Queen Village said she expected Jedi fighters to appear on the video wall with the image of the cosmos. She said she found the fish in the aquarium "tranquil."

Roberts said the idea of the video wall came to him during visits to Asian consumer-electronics companies. At Panasonic, Roberts recalled a woman tapping a wall, and video coming to life. The woman moved the video to another place on the wall with her hand.

Wow, thought Roberts.

At Samsung, a company official snapped a picture of the group he was with and displayed it on the wall. That was cool, too. Sony has a place in its headquarters where it shows off its latest products.

Was it too edgy, Roberts wondered, and would Comcast employees be comfortable with it? Stephen Burke, Comcast's chief operating officer, suggested showing original content. No CNN, or ESPN, MTV, Showtime or Golf Channel.

Comcast commissioned New York content designer David Niles, of the Niles Creative Group, to create the vignettes. Then Roberts asked about 30 top executives to rate them for changes and final selection. Barco Inc., with U.S. headquarters in Rancho Cordova, Calif., manufactured the LED screen and its processors.

"When you're looking at this, you're seeing computers interacting with video libraries that are controlled by a content-delivery system," Roberts said. "It's imaginative, and it lets people escape from their daily lives and allows them to glimpse into the future. It's a much better feeling than looking at the wall and seeing traditional TV."

Added Roberts, "It felt right to take a leap and say 'Let's do something that hasn't been done.' "

Contact staff writer Bob Fernandez at 215-854-5897 or bob.fernandez@phillynews.com.