Radiohead's Thom Yorke. Photograph: Leon Neal/AFP/Getty
Before it had even arrived in the world's inboxes, you would be hard-pushed to call Radiohead's seventh album anything other than a triumph, at least of marketing. The honesty box approach meant In Rainbows was discussed in areas not usually noted for their interest in leftfield gloom-rock. It turned up in a broadsheet's economics section, while one can only begin to imagine Thom Yorke's untrammelled joy at the piece by an advertising executive, which claimed the singer's paralysed left eye was "the perfect analogy" for Radiohead's expertise in branding.
Elsewhere, the band's creative partner, artist Stanley Donwood rattled the collecting tin a bit, pointing out the album's lengthy, agonized gestation, which at one point entailed fraught discussions about splitting up. This is hardly an extraordinary state of affairs - no Radiohead album really feels complete without an agonized and fraught gestation, in much the same way that no R&B album feels complete without an interminable thank you list in which God features heavily but, on listening to In Rainbows, it seems surprising.
This does not sound like a band clutching their brows and wondering what to do next. The lyrics may be as neurotic as ever you're never that far from an infrastructure collapsing or the lights going out or being eaten by the worms - but as it flows seamlessly along it sounds supremely confident, like a band who know they're at the height of their powers. There's nothing tentative even about its more experimental moments, possibly because even its more experimental moments - 15 Step's clattering beats, the unsettling electronic pulse behind House Of Cards - are pressed into the service of fantastic melodies: the closing Videotape proceeds at the pace of a Soviet state funeral, but the tune is so glorious, it sounds graceful rather than lethargic, dreamy rather than dreary. Radiohead sound like they're enjoying themselves, not least on Bodysnatchers, which features a geefully propulsive bass riff. In the parlance of the middle American sports stadium crowds with whom Radiohead have such a troubled relationship, it rocks.
The most heartening thing about In Rainbows, besides the fact that it may represent the strongest collection of songs Radiohead have assembled for a decade, is that it ventures into new emotional territories: their last album, 2003's Hail to the Thief, had its moments, but it was scarred by the sense that the band's famed gloominess was starting to tip into self-parody and petulance. Here, there's wit - at 15 Step's conclusion, Yorke's patented end-is-nigh keening is undercut by a childrens' chorus merrily crying "hey!" - and warmth. With its strings and swooning guitars, Nude sounds lushly romantic. So does All I Need, which, moreover, ends in a fantastic, life-affirming crescendo. Witty, romantic, life-affirming: you don't need to be an expert in the minutae of their back catalogue to know that these are not adjectives readily associated with Radiohead. But then, in the years since OK Computer propelled them to superstardom, you could say the same about the phrase "consistent album", yet that's precisely what In Rainbows seems to be. Whatever you paid, it's hard to imagine feeling short-changed.
· Visit our 15 years of Radiohead photo gallery. · Visit our gallery of Radiohead cover art. · Paul Morley is live blogging the album here.