By Niall Murray

U2 will have the biggest audience of their careers when almost a billion television viewers watch their half-time performance at the Superbowl on Sunday.
The four-member band will be leaving all their planning troubles behind when they take the stage at the Louisiana Superdome in New Orleans in the middle of the clash between New England Patriots and the St Louis Rams.

After legal representatives tried to save their Dublin quayside recording facilities from demolition this week, the group's minds will be far from recording at the weekend.

Their crew will have six minutes to set up the Elevation tour stage in centrefield to allow the band perform three songs, which have not been announced yet.

The Superbowl slot is coveted more for the global exposure it provides than the financial rewards, according to Keith Spera, music writer with New Orleans newspaper Times Picayune.

"I haven't heard any figures at all as far as U2's Super Bowl paycheque is concerned but they might do it for less than you'd think, given the promotional value," he said.

At a press conference in New Orleans on Wednesday, Bono and The Edge joked they were not going to talk about the New England Patriots team news. Instead, they told reporters they were in town to spread peace and understanding.

American diva Mariah Carey will be returning to the spotlight after a recent breakdown, when she sings US national anthem The Star Spangled Banner before the game begins.

U2 are following in the footsteps of Aerosmith, Phil Collins, Stevie Wonder, Boyz II Men and James Brown as half-time Superbowl entertainers of the last five years.

Only the Rolling Stones $121m (€140m) 1994 tour earned more for a rock band than the latest U2 roadshow. The Irish supergroup sold out more than 100 shows on the Elevation tour, which earned them around €127m. They have already sold more than 10m copies of their most recent album, All That You Can't Leave Behind, which topped the charts in more than 30 countries.

They are believed to have begun recording tracks for their next album at the Hanover Quay studios, which the Dublin Docklands Development Authority (DDDA) wants to demolish as part of a renewal of the Grand Canal Dock.

Minister for Tourism Jim McDaid said this week he was concerned about the implications of knocking the building, although he was not familiar with the exact nature of the matter.

"U2 are a major attraction for visitors to this country and we have to proceed very carefully with anything involving them," he said.

A decision on the band's objections to the DDDA's compulsory purchase order on the studios is due from An Bord Pleanála in April.