Swift sang some of her best known songs on Tuesday night, accompanying herself with either a guitar or a piano. The set list, made up of "Style", "Delicate", "Love Story", "New Year's Day" and "Shake It Off", covers a wide span of Swift's career, going all the way back to 2008.
The singer's acoustic set contrasted with her Reputation aesthetic. For that album, as well as for the accompanying tour, Swift seemed to fully lean into her pop star persona, while still acknowledging her country roots during live performances.
Swift's style on Tuesday (a long, vaporous strapless gown and a romantic hairstyle) was also a departure from the edgier outfits she favoured during the Reputation era, and can be seen as a throwback to earlier, pre-pop stages in her career.
These changes haven't gone unnoticed by the singer's ever-observant fans, who now believe that Tuesday night's appearance could constitute a preview of what's to come when Swift releases her next album – which they currently refer to as TS7.
"Based on her acoustic performance at Time 100, I think that Taylor will DEFINITELY be incorporating more guitar in her album," one person tweeted. "If Reputation is her experimental album (like Lady Gaga's Art Pop), then TS7 will be a stripped down album (like Lady Gaga's Joanne)."
"So Taylor sang acoustic versions of old songs last night, WHAT IF TS7 IS A SOFT ACOUSTIC MOOD," someone else wrote.
One person suggested that Swift's next album could even be comprised of acoustic covers of some of her most popular tunes.
Swift appeared to tease forthcoming new music earlier this month, when she shared a mysterious countdown to 26 April on social media.
She has since continued posting one photo per day on Twitter, always with the message "4.26". All the images feature soft pastel hues in keeping with Swift's look on Tuesday night – painting a more complete picture of the aesthetic she might deploy on her next album.
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