As the massive, 24-hour, multi-continent, Live Earth [ tickets ] concert approaches, organizers have announced two more cities and are drumming up excitement with a new website and exclusive content, including a free Madonna [ tickets ] song written for the occasion.

In addition to previously announced concerts in the New York area, London, Sydney, Tokyo, Shanghai, Johannesburg and Rio de Janeiro, Live Earth now has planned shows in Hamburg and Istanbul.

Beginning today (5/17), fans can download the new Madonna [ tickets ] tune "Hey You" from Live Earth [ tickets ]'s website. The song will be available free for seven days, and MSN will donate 25 cents for each of the first 1 million downloads to the Alliance for Climate Protection.

The Alliance is one of the non-governmental organizations that will benefit from the July 7 Live Earth concerts, which will host more than 100 acts across all seven continents in an effort to bring attention to the climate crisis.

"On 7/7/07, Live Earth will inspire people from around the world to combat global warming with live performances from superstar artists like Madonna," Live Earth founder Kevin Wall said in a statement. "The early release of 'Hey You' is an incredible boost to our efforts to get people engaged in the environmental cause. We are thrilled that Madonna donated her art to Live Earth and is a part of this movement for us."

Initial lineups have been announced for Live Earth shows in the US, UK and Australia. The event's finale will take place at New Jersey's Giants Stadium with The Police, Roger Waters, Smashing Pumpkins, Kanye West, John Mayer, AFI, Kelly Clarkson, Akon, KT Tunstall, Alicia Keys, Ludacris, Bon Jovi, Sheryl Crow, Melissa Etheridge, Dave Matthews Band, Rihanna and Fall Out Boy.

Performers at London's Wembly Stadium include Beastie Boys, Black Eyed Peas, Bloc Party, Corinne Bailey Rae, Damien Rice, David Gray, Duran Duran, Foo Fighters, Genesis, James Blunt, John Legend, Keane, Madonna, Paolo Nutini, Razorlight, Red Hot Chili Peppers, Snow Patrol and legendary fake rockers Spinal Tap.

The event will kick off at Sydney's Aussie Stadium with Crowded House, Jack Johnson, Wolfmother, John Butler Trio, Missy Higgins, Eskimo Joe, Sneaky Sound System, Paul Kelly, Ghostwriters, Toni Collette & the Finish, and Blue King Brown.

The performances will stream live at the event's website and will also air on television and radio stations worldwide. Organizers expect an audience of 2 billion.

Following the concerts, Warner Bros. Records will release a live CD/DVD, according to a press release. A companion book written by environmentalist David De Rothschild, "The Live Earth Global Warming Survival Handbook: 77 Essential Skills to Stop Climate Change," is also due June 26, according to the Associated Press.

Live Earth is the first event produced under the banner of Save Our Selves (SOS), an organization formed by Wall, former Vice President Al Gore, rapper/producer Pharrell Williams, actress Cameron Diaz and the MSN Network. SOS aims to trigger a new level of global response to climate change by using its members to reach people worldwide via television, radio, film and the Internet, according to a statement.

In related news, the organizer of the massive Live Aid and Live 8 concerts, Bob Geldof, has reportedly criticized the Live Earth events, saying they lack a specific goal.

"I hope they're a success," the singer/songwriter/actor was quoted as saying in an interview with Dutch newspaper De Volkskrant. "But why is [Gore] actually organizing them? To make us aware of the greenhouse effect? Everybody's known about that problem for years. We are all [expletive] conscious of global warming."

Geldof, who organized Live Aid in 1985 to benefit Ethiopian famine victims and Live 8 in 2005 for African debt relief, added he would only put together an event like Live Earth if he could announce concrete environmental measures.

"They haven't got those guarantees, so it's just an enormous pop concert or the umpteenth time that, say, Madonna or Coldplay get up on stage," Geldof told the paper.

He also criticized Live Earth's name.

"It sounds like Live 8," Geldof reportedly said. "We're getting lots of responses from people who think we are organizing it."