Fotopedia.comIf we’re going to save this rock, we might have to save the Earth Summit in Rio next year first. I've got good news and bad news about the future of the planet. Good news first. Next year, a honking big global Earth Summit is coming our way -- one with a proud heritage. Formally titled the U.N. Conference on Sustainable Development, the meeting is known as RIO+20 because it will come 20 years after the first Earth Summit in Rio in 1992. That original Earth Summit (itself 20 years after the equally important Stockholm Convention on the Environment …