Martian Life - Is It?

The Sun has an article about a big NASA press conference today, where it will be revealed that large clouds of methane gas have been confirmed to exist on Mars, usually in the same areas as clouds of water vapour. This is significant, because the two main causes of such amounts of methane are volcanoes (Mars doesn't have any active volcanoes) and biological waste.

How awesome is this news? What does this mean for the likelihood of life evolving on extra terrestrial bodies? Is it coincidence, or does it mean it is more likely than many scientists have previously thought? Did life on the two planets evolve separately, or was one planet seeded from the other, as some theories have suggested? Or from comets? So many questions! One thing is for certain, if this does indeed lead to the discovery of microbes on Mars, surely it changes our perspective on ourselves?