Rock band the Klaxons have won the Nationwide Mercury Prize for the best album of the past year, beating Amy Winehouse and the Arctic Monkeys.
The "new rave" group from south London scooped the £20,000 prize for their debut Myths of the Near Future.
Singer Jamie Reynolds said they deserved to beat Winehouse because she made a "retro record and we've made the most forward-thinking record".
Winehouse performed at the ceremony, her first appearance for several weeks.
She gave a breathtaking rendition of Love Is A Losing Game from her nominated album Back To Black - but it was not enough to win her the award.
There was uncertainty over whether she would even turn up after attending rehab following reported drug use.
Amy Winehouse performed amid speculation about her health
Speaking after the show, her father Mitch said: "She was very happy to be here. And I'm just thrilled she was here. She gave a brilliant performance and she looks well."
Klaxons, who have only been together for two years, looked elated as they hugged and ran on to the stage to collect their award from Jools Holland.
Guitarist Simon Taylor-Davis told BBC Radio Five Live's Breakfast the publicity surrounding Winehouse made the band feel "even more excited" about their success.
"I just felt sorry for her. She probably felt embarrassed yesterday, with all the palaver about her," he said.
The Mercury Prize judges said the group took them on an "ecstatic musical adventure".
Their album, which features the singles Golden Skans and It's Not Over Yet, reached number two when it was released earlier this year.
NME editor Conor McNicholas, who was on the judging panel, said Winehouse's performance at the ceremony was "amazing".
"I've never been to an awards ceremony where somebody has performed and the room has been genuinely silent, proper pin-drop stuff," he said.
"But we have to take into account an awful lot and at the end of the day the Klaxons was felt to be the right decision.
"It's an album that could only ever have been made in Britain, could only ever have been made at this moment in time and it's a multi-layered album."
Bat for Lashes had been the bookmakers' favourite to win
Winehouse's album was "one of the greatest vocal performances this country has ever seen", he admitted.
But he added: "You can argue that ultimately it is a backward-looking album and one of the things Klaxons have tried to do is produce something that feels like it came from the future."
Winehouse's personal problems did not factor in the decision, he said. "I can honestly say it genuinely comes down to just the music on the album - everything else is shut out of that room."
Last year's winners the Arctic Monkeys were nominated for their follow-up Favourite Worst Nightmare. But the Sheffield band did not attend the ceremony because they are on tour in the US.
Rapper Dizzee Rascal, who won the award in 2003, was also up for the prize, as was singer-songwriter Natasha Khan, aka Bat For Lashes - the bookmakers' favourite.
Band consists of Jamie Reynolds, James Righton, Simon Taylor-Davis and Steffan Halperin
Debut album Myths of the Near Future reached No 2
UK tour planned for November - December 2007
Golden Skans reached No 16 in the UK singles chart on download sales alone
Came 3rd in BBC Sound of 2007 poll
The shortlist was an eclectic mix again this year, ranging from Leicestershire indie trio The Young Knives to classical quintet Basquiat Strings.
Other nominees included Fionn Regan, New Young Pony Club, The View, Maps and Jamie T.
Ladbrokes spokesman Nick Weinberg said the company was "pleased" to avoid having to pay out on a Bat For Lashes win.
But Klaxons frontman Reynolds put a £100 bet on his band to win at 9/1. After a night of celebrating, he was unable to appear on BBC News 24 as planned on Wednesday morning.