"I'm sorry if my business attire is a little different," she joked as she shook hands with staff.
Gaga took charge of the morning editorial meeting, offering her opinion on a range of topics from bullying to the Japan earthquake to who her heroes are.
She immediately set out her vision for the paper in her role as guest editor for the day, touching on themes she has already mentioned as part of her mission as an entertainer.
"I feel so privileged I get to make music every day," she told staff. "If you have revolutionary potential you have a moral obligation to make the world a better place."
Her new record is the follow-up to her 2008 debut album "The Fame", which went on to sell more than 12 million copies and topped the charts. An extended play release "The Fame Monster" came out the following year.
Gaga, whose real name is Stefani Germanotta, has a huge and famously devoted fanbase around the world whom she calls her "little monsters".
In turn she refers to herself as "Mother Monster" whose every public appearance is a piece of performance art and outlandish fashion statement rolled into one, turning her into a cultural phenomenon as much as a musician.
"I really appreciate the opportunity and it's a wonderful chance for me to show the world that little monsters are not just a fan thing, but exist outside the music world altogether," Gaga said of her editing activities at Metro.
Gaga's more notorious outfits to date have included a raw meat dress she wore to the MTV Video Music Awards last year and her arrival at the Grammy Awards in February encased in a giant egg.
"I'm half living my life between reality and fantasy at all times," the "Just Dance" and "Poker Face" singer recently told the Guardian newspaper. "It's best not to ask questions and just enjoy."
It is not all just about enjoyment, however, and music writers and commentators who have interviewed the singer note a messianic dimension to her ambition which appears to go beyond merely selling records.
Her own online biography concludes: "And, now, I'm just trying to change the world one sequin at a time," albeit with "a wink in her eye."
It is not all plain sailing for the multi-Grammy Award winner, however.
The huge impact of "The Fame" means the pressure is on for "Born This Way" to match that commercial and critical success.
Religious groups accuse her of blasphemy, there was dissent in the ranks of her legions of fans over the cover art to Born This Way and she has reacted angrily to suggestions that the first single from the new record was copied from Madonna's 1989 hit "Express Yourself".
(Reporting by Mike Collett-White, editing by Paul Casciato)
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