Taylor Swift Shakes Off the 'Frenemies' During iHeartRadio Fest Performance: Watch

Taylor Swift is a different artist than she was two years ago, which was the last time she performed at the iHeartRadio Music Festival in Las Vegas. Like her 2012 performance, Swift's five-song set on Friday night (Sept. 19) consisted of three past hits, then early treasure "Love Story," and then her flashy new single (at that point, "We Are Never Ever Getting Back Together"). But instead of taking the stage at the MGM Grand Garden Arena as country's undisputed queen, Swift opened this year's show as a music superstar pivoting unambiguously toward pop music, an effort restated through another live performance of her new smash "Shake It Off."

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"So here we are, all of us in Las Vegas, because we all love listening to the radio," Swift told her audience a little after 7:45 PT on Friday night. Twirling around the stage in a jewel-encrusted light pink two-piece, Swift's performance was pure bubblegum, as she blasted through her most sugary Red hits ("We Are Never Ever Getting Back Together," "22," "I Knew You Were Trouble.") and then thickened the country-pop of "Love Story" into a blustering arena-rock opus. Meanwhile, a 13-piece backing troupe rounded out her giddy vocals, and the numbers '1 9 8 9' towered onstage behind her, a constant reminder that a new T-Swift era is about to begin.

The too-short set -- and one, disappointingly, with no previously unheard songs previewed -- ended with "Shake It Off," which Swift introduced as a product of trying to de-stress and take down the naysayers. "If you have frenemies and if you have liars and dirty dirty cheats of the world… I think the best way to handle a situation like that is just to shake it off" (a Katy Perry subtweet, perhaps?). When the song began with the four-piece brass section kicking in, Swift appeared elated to be able to play her new confection for the first time since the MTV Video Music Awards, and "Shake It Off" easily elicited her highest energy level of the night. While the iHeartRadio audience was busy dancing, Swift came over to her trombonist and puckishly smacked his ass as if he were one of her well-publicized haters

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"I was so happy tonight, it made it impossible to remember the times in the past that I haven't been," Swift tweeted a few hours after the performance. Swift will likely explore those unnamed demons on new album 1989, due out Oct. 27, but as iHeartRadio Fest's opening act, she was a high-energy champion with a shiny new toy to show off.