Béria Lima changed the image back to the original "On the Edge" graphic.
Given that there are some people who think I abused my staff status and/or didn't wait for consensus, I think I will bow out at this point, rather than get into a revert war on the Main Page.
(However, note that the captions are now all wrong in other languages -- some of them were updated in the meantime to reflect the Amazonian image.)