Live Earth, not simply because of the artists that performed, but also because of the way it was done. There were less commercials, less VJ interruption, and it did a better job of explaining the cause and telling everyone what to do about it. All in all, I think live earth will be more successful. Although I see that I'm in the minority here.
live earth, it was the first of it´s kind...if the planet goes on like this, we will have hundreds of millions of climate refugees, insurance companies going bankrupt, no infrastructure, global kolera and other diceases....we´re heading towards doomsday, but it can be hindered if we do something (madonna, you start! )