There are signs of progress at the Rotunda, which was built in the 1920s for Maryland Casualty Insurance Co. and partially converted to a shopping center in 1971.
Ira Miller, who took over the twin-screen Rotunda Cinemas in 2010, has since added a third screen, and said he will add a fourth in the old Tomlinson Craft Collection space.
Rotunda merchants are also encouraged that Johns Hopkins University bought the former Zurich office building next to the mall and is moving in about 1,125 employees, who may bring much-needed foot traffic to the mall.
Hopkins bought the Zurich building with the convenience of the mall in mind, said university spokesman Dennis O'Shea.
"We certainly would love for there to be amenities for our employees," he said. "By having a substantial employee base [nearby], we certainly add to the attractiveness of the space."
But Rotunda merchant Sheldon Pearlman remains skeptical about a major redevelopment.
"My gut feeling is there is no redevelopment [coming], even though they swear it is," said Pearlman, owner of Amazing Spiral (formerly Comics Kingdom) in the mall.
Chatting behind the Casa Mia's counter the day before Giant's announcement, Malik, a 64-year-old native of Pakistan, was thinking less about redevelopment than about an increase in outside competition. A gourmet burger truck, Kooper's Chowhound, sits near the Rotunda's back entrance several days a week.
Malik, whose eatery has been in the Rotunda for more than 11 years, is critical of management for allowing mobile food vendors to sell in the parking lot, where he says they take business from him.
"We hung out waiting for the good times," said Malik, "and then this happens."
Rotunda property manager David Bouchard could not be reached for comment about the criticism.
Some merchants said that the mall's mix of retail and office space, including a Christian Science Reading Room with limited hours, and a Social Security Administration office, does not generate many customers.
But Pearlman said moviegoers stop in his store, and so do people going to doctor's appointments. "It definitely attracts business," Pearlman said.
Giant is not the first major tenant to leave the mall. Stores that have left in the past decade include Tomlinson, Rotunda Liquors and Bank of America. Most of the spaces are still empty.
"It would be really nice if they got a bank back," Pearlman said. "Losing Bank of America hurt."
But merchants can take heart in longtime customers such as Rosetta Miller, who ate a late lunch last week at Casa Mia's after buying pants and hats in the mall.
The Hampden resident, 65, who doesn't drive, said the mall has been a one-stop center for all her shopping and medical needs.
"And this is the best place to eat," she said.
Sun reporter Lorraine Mirabella contributed to this article.