The most likely explanation for life on Mars is contamination between Earth and Mars, though that says nothing about ultimate origins. Hoyle, an atheist wh later became an agnostic, believed it was intelligent design.
One thing to keep in mind is that NASA not only wants but needs to see life. We are in the midst of a financial meltdown in which people are losing their homes and jobs, the price of food is rising across the globe, and the expensive Mideast conflict rages on. NASA is an expensive operation. If Mars were doubted to have life, that could impact its budget.
Here's NASA's release: "The Red Planet is not a Dead Planet":
Methane -- four atoms of hydrogen bound to a carbon atom - is the main component of natural gas on Earth. It is of interest to astrobiologists because much of Earth's methane come from living organisms digesting their nutrients. However, life is not required to produce the gas. Other purely geological processes, like oxidation of iron, also release methane. "Right now, we don't have enough information to tell if biology or geology -- or both -- is producing the methane on Mars," said Mumma. "But it does tell us that the planet is still alive, at least in a geologic sense. It's as if Mars is challenging us, saying, hey, find out what this means."Find out what this means, and don't cut the budget!
The release finishes with "Whatever future research reveals - biology or geology - one thing is already clear: Mars is not so dead, after all."
Equating life to rocks is, at the very least, a most unusual interpretation of not being "dead." Having not definitely found life in the rocks of Mars, they now imply that life, rocks, it's all the same. People in this state of mind should be heard with patience ... but also with prudence.
Here's Fuz Rana's view, giving reasons why the methane is more likely geochemical than biological in origin.