Methane = Life?

Detection of methane in the martian atmosphere: evidence for life?

"Outgassing from Mars is weak, the latest volcanism is at least 10 million years old, and thermal emission imaging from the Mars Odyssey orbiter does not reveal any hot spots on Mars. Hydrothermal systems can hardly be warmer than the room temperature at which production of methane is very low in terrestrial waters. Therefore a significant production of hydrothermal and magmatic methane is not very likely on Mars."

I love sober scientific abstracts. The sentence above is essentially a "polite" way of saying "Atmospheric methane on Mars can only be coming from an active biosphere."