First Night: V Festival, Hylands Park, Chelmsford

Rihanna treats festival to a different kind of girl power

Wearing a midriff-baring denim shirt and encrusted leather hotpants Rihanna swings her head of auburn curls with fearless tenacity as she arrive on stage singing her preposterously beguiling trance-pop tune "Only Girl (In The World)". Except she doesn't just arrive onstage, she arrives onstage dancing against a pole before hurtling through hits including "Shut Up and Drive", "Disturbia", "Rude Boy" and even a version of "Redemption Song".

It's a wildly engaging show; there's something undeniably unique about the way she exploits the Barbadian grit of her voice and all the songs are laden with catchy pop hooks; from the anthemic "Man Down" to the slick, shadowy tectonic rhythms of "What's My Name?" But as she grinds and gropes her way around the stage it's clear her gift to the UK festival scene is not really her music, it's her fearless exhibitionism.

While she might want you to make her feel like she's the only girl (in the world), she's actually not the only girl (headlining a UK festival this year); Beyonce wowed Glastonbury with a fierce performance complete with fireworks and hydraulic staging. But the delight really came from the visceral power of her voice. Watching Rihanna straddle a gigantic pink cannon while her backup dancers carry pink rifle guns it seems that while Beyonce's headlining festival performance was an example of fierce entertainment, Rihanna's is one of brash self-promotion. If the Destiny's Child superstar sits one side of the befuddling line between sexual empowerment and objectification, Rihanna sits on the other.

Visually the Essex festival seemed to have toned down its corporate advertising this year, although standing at the Virgin Media Stage in the rain on Saturday watching a mob coo along with Bruno Mars's syrupy pop hook "I wanna be a billionaire so frickin' bad, Buy all of the things I never had" did feel like an unsettling insight into a dystopian future. But spirits soared when the sun burst out for an afternoon of high-energy sets: Example riled the crowd with his electro pop and pummelling synths, before Jessie J, with a broken foot, delivered an utterly compelling performance from a chair. More mobile, but equally energetic, rapper Tinie Tempah later span across the same stage, sending the crowds wild.

Such hysteria is synonymous with big pop gigs, but this year's V was more pop than ever. Indeed, reflecting on headlining this year, Arctic Monkeys revealed that they felt a sense of responsibility to keep guitar music alive. But if they really want to be the saviours of guitar music, they will have to try harder: even the psychedelic fills on "This House Is a Circus" were not enough to make up for their lacklustre stage presence.