Brisbane’s QSAC has become one enormous U2 anthill as the much-awaited and long-delayed Australian leg of the Vertigo tour finally rolls into town. Some 45,000 fans – young and old – have been waiting six months and more, and it’s a visceral thrill to wander into the arena and behold the five-storey tall twin speaker stacks resplendent with Vertigo’s red-and-black diagonal slashes – each surmounted by massive LCD screens.

But, eager as the crowd is for U2, they’ll have to wait just a little longer while Grammy Award-winning rapper Kanye West struts his stuff centrestage. Kanye only has one problem – the sound isn’t working to his advantage.

He’s brought along a five or six-piece string section – violins, cellos, even a harp – to fill out his sound, but the subtle nuances and lush orchestral layering is muffled by the inadequacies of the sound setup. From the stands at least, even his rapid-fire lyrics are difficult to distinguish at times.

Nevertheless, Kanye works gamely throughout the set and at the front a hardcore knot of fans pump the air with their fists. Early on, some sampling of Eurythmics, Moby and The Verve creates intrigue. Heard ‘em Say and Jesus Walks are well received, but the crowd perks up the most to the familiar strains of the brassy-bluesey hit Gold Digger. By the time he and his posse conclude with Touch The Sky we’ve consumed an intriguing appetiser for the main act. Can’t help but feel it would be much more enthralling in an intimate club setting, though.

A break of almost an hour gives us plenty of time to digest Kanye’s set. Perhaps a little too much, in fact, because a Mexican wave begins ringing its way around the stadium at one point. Surely a sign of restlessness.

However, all delays are forgiven the moment U2 hit the stage. They proceed to prove the ‘best band in the world’ moniker is well deserved with a sublime performance that belies the immense technical and logistical difficulties of entertaining so many. The band is tight and energetic, the sound is unbelievably crisp and the LCD screens create an intimacy that you wouldn’t expect to enjoy at the farther reaches of the stadium. More, as the set proceeds, they skillfully invest their act with a powerful message of social justice activism that is intensely personal, but never too preachy. It’s part rock concert, part an impassioned plea to humanity – and completely spellbinding from start to finish.

From the get go, the front third of the crowd is a sea of waving arms as the band begins with City of Blinding Lights. Vertigo follows, and stunning light and visuals provide the literal interpretation of the track title. Disorienting patterns of vivid black and red – stripes, hearts, targets, circular bands – vie with blinding streaks of yellow light that flash repeatedly across the stage. Surely an epileptic’s worst nightmare, but signature U2.

Highlights are thrown up everywhere. Elevation features a mid-song breakdown into a gritty version of The Go-Betweens classic Streets of your Town – the first of two touching tributes to the late Grant McLennan. And from the beginning, hardly any cajoling is needed to get the crowd going ‘Oooh, oooh’ even if no-one can match Bono’s falsetto.

There’s also a quick dip into the back-catalogue early on. First it’s Achtung Baby’s Until the End of the World and then we’re treated to some vintage U2 with War’s lead single New Year’s Day. The crowd laps up The Edge’s shimmering, skittering guitar as it glides over and under Bono’s vocals.

Then a spine-tingling rendition of Beautiful Day somehow manages to encapsulate the joy of being alive in five glorious minutes of perfect pop-rock. Even more than the studio version – listening to Bono sing his heart out while the screen behind morphs repeatedly from a bright blue into a deep burnished gold reminiscent of a fading sunset – you can’t help but feel that it really is a beautiful day.

Sometimes You Can’t Make it on Your Own – dedicated to Bono’s late father – tugs at the heart with its achingly personal lyrics, and probably fares the best of all the songs from How to Dismatle an Atomic Bomb. However, Yahweh, with only The Edge supporting Bono on acoustic guitar, and the sleazy, bass-driven and ridiculously bombastic, Love and Peace or Else both benefit from the additional intensity that live performance lends to them.

The latter climaxes into Sunday Bloody Sunday, and twenty-plus years haven’t dimmed the song’s rhetorical force in the slightest. The word ‘COEXIST’ materialises on screen – the C as the crescent of Islam, the Star of David forming the X, and the Christian cross as the T. With Larry Mullen Junior’s military-esque snares driving the rhythm, Bono uses it as an opportunity to call for David Hicks to be brought back to Australia to face justice. “We don’t have to become a monster to defeat a monster,” he insists.

From there, the social justice message flows thick and fast. Bullet the Blue Sky – complete with a diversion into Johnny Come Marching Home Again - becomes a prayer for ‘the troops’ to come home safe. Miss Sarajevo is a haunting plea to respect human rights. Its piano notes linger and echo over the stadium and the crowd hushes. Bono is no Pavarotti, but he fills in on the great tenor’s part more than adequately. And when the text of the Universal Declaration of Human Rights scrolls up the screen at the conclusion of the song – read out by a child of about ten – the effect is spine tingling.

Pride (In the Name of Love) and Where the Steets Have No Name form a dual ode to Bono’s best-known passion as he exhorts us all to sing for the African dream. They close out with a stellar version of One. Bono coaxes everyone to pull out their mobiles. Some 45,000 glowing LCD screens proceed to turn the stadium into a large-scale replica of the Milky Way as the activist frontman turns an idle observation on the power of the humble ‘cell phone’ into a powerful request to support the Make Poverty History campaign. “If enough people talk, politicians have to listen because there’s nothing we can’t do if we act together as One.”

They depart, but not for long. A standing ovation draws the Irish quartet back and they proceed to reprise their Zoo TV days with Zoo Station and The Fly. Streets of Your Town makes another appearance during With or Without You. The simplicity of Bono’s dedication: “For Grant McLennan, who died” is beautiful.

The crowd is also treated to a cover of The Skid’s The Saints Are Coming - a song U2 first performed only recently at a Hurricane Katrina benefit with Green Day. Then, just to make sure everyone is dancing in the aisles, they dust off a harmonica-fuelled rendition of Angels of Harlem and round out the two hour-plus gig with a gorgeous version of Kite. And as Bono releases a vividly coloured paper bird into the night sky (drawn aloft by balloons), we all fervently hope this is not goodbye. Bono seems to be pretty sure it isn’t.