"This place is so little!" exclaimed Norah Jones as she sat down at her piano on Saturday night in front of a crowd of 300 BBC Radio Two competition winners. And you could hardly blame her. For an artist who sold 20 million albums and won eight Grammy awards in 2003, the London Symphony Orchestra's St Luke's concert hall must have seemed rather small-time, despite its imposing design and supremely tasteful lighting.

Jones eschewed big hits in favour of tracks from her forthcoming album. Opening with Cold, Cold Heart, whose mournful melody was complemented by exquisitely sparse use of the double bass and Jones's equally judicious piano work, she mesmerised the fans right from the start.

There was, however, a peculiar atmosphere - partly the result of the fact that it was being recorded for broadcast. She made little eye contact and offered minimal inter-song banter.

Still, there was a certain thrill in the show's lack of polish. After all, it's not every day you get to see Norah Jones strolling around sipping a cup of tea or stopping a song halfway through to discuss a mistake with her band.

In any case, such grumbles paled into insignificance in the face of her singing, the quality of her new material, and her band's array of inventive arrangements.

One particular delight was Broken, a cheeky waltz on which the double bass player created an atmospheric "loop", using an effects pedal to record the sound of a bow on the strings. The jazzy, honky-tonk flavour of Sinkin' Soonwas enhanced by the sharp crack of the drummer hammering on a wooden crate.

Classic-sounding, melodious and never loud or threatening, Jones's music is undoubtedly a perfect fit with the Radio Two music policy. But it would be ignorant to write her off as a purveyor of bland "coffee table music".

On Saturday night, she and her band were anything but boring, showing exhilarating levels of subtlety and inventiveness in rhythm, dynamics and the use of instruments.

Norah Jones may be characterised as middle of the road, but her performance demonstrated beyond doubt that her place on tens of millions of coffee tables is well deserved.