Glastonbury Festival, Worthy Farm, Somerset

When Damon Albarn starts to grin five songs into their great Glastonbury comeback, Blur start to look like a band again. And when he breaks down weeping near the end, you know how much it meant. "Beetlebum" is the song where Albarn's errant guitarist and childhood friend Graham Coxon fizzes up his effects pedals, bassist Alex James starts to spin, fag dangling, and you remember Blur were the 1990s' great psychedelic band.

When they begin with debut single "She's So High", by contrast, Albarn is glassy-eyed and pumped-up, and singing with the deep doom of Joy Division's Ian Curtis. "Tracy Jacks" is all throaty aggression, and you wonder if he'll really be able to sing at all. After "Beetlebum" clears his mind, though, he finds himself singing "Out of Time", about the awful 2003 split with Coxon, who is now playing it.

And during "Trim Trabb" it is Coxon, writhing on his back, who hilariously sheds his large inhibitions. When the vast crowd keep singing "Tender" after Blur have finished their own epic version, the band look at each other with happy wonder. Phil Daniels reappears for "Parklife", of course, with Albarn sprinting giddily as its defiantly lazy chorus is roared out again.

It is just before "This Is A Low", the best of Albarn's often deeply personal songs, that he sits on the stage and weeps, utterly overcome by all the times that have just been unstopped. Getting up to sing it is almost heroic.

Sunday builds slowly to this crescendo, with the day's traditional, jokily received old-timers, led by orange-skinned, irrelevant Tom Jones. But a crowd still largely alert despite briefly drinking the festival dry of cider give more attention to Yeah Yeah Yeahs' Karen O. Her psychedelic pixie dress and piercing screams don't concern her archetypal New York guitarist Nick Zimmer, whose vampiric pallor looks set to turn to ash in the sun. Amadou and Mariam meanwhile let Mali blues guitar snake out in gently winding shapes, and Madness, an English band almost as great as Blur, roll out their own warm, bonding pop.

Bruce Springsteen's marathon UK festival debut is the pre-Blur story. He walks on with superhuman confidence recalling Barack Obama's eerie ease. He has expensive cowboy boots for the Glastonbury mud, and changes guitars like F1 pit-stops. For an hour and fifteen minutes he ignores any idea of a "festival set", nervily playing no hits.

This lets you notice how camp "Outlaw Pete" is, and his ironic testifying style, where once he preached with halting honesty. "We want to build a house, here on this field!" is also an unfortunate metaphor which may have Michael Eavis reaching for his shotgun. But then he breaks the hit floodgates with "Because the Night", as the dark falls on a relieved crowd.

Bush protest "Lonesome Day" has the platitudes of an observer, not the personally desperate edge of 1978's gasped "Promised Land". But "The Rising"'s fireman whose horizon folds under the Twin Towers is powerfully followed by "Born to Run"'s wide-open future. By "Glory Days", everyone around me is spontaneously dancing to rock'n'roll, which is what it was for when Bruce Springsteen was young. But the E Street Band sound stiff compared to Blur.

Dizzee Rascal is a weekend hits, proving how trumped up last year's Jay-Z controversy was. "Sirens"' inner-city estate pursuit is incongruously exciting in a field where the question "Where's all the G's [gangsters]?" causes shifting feet. Dizzee lets DJ Semtex play "Thriller" through as his Jackson tribute. There's no gap in the relentless fun this worldly Bow pop star gives.

Nearby, you can for once say the same for Pete Doherty. He can't quite run the pro-pop band he's been handed by his label, but he has a ragged charm that can't be corralled. Florence and the Machine is visibly moved at the acceptance of a crowd spilling well outside the John Peel tent, and Emmy the Great, with folky variety recalling Sufjan Stevens, is equally striking.

But is Blur, and Damon Albarn's tearful wrestling with his own Glastonbury moment, that makes this year's festival great.