This report is from Reuters: "Mars Once 'Drenched with Water,' NASA Says." According to a related report,
NASA scientists say the robot hasn't found any direct traces of living organisms, but they say the findings suggest that if life had been present when the rocks were formed then the living conditions could have permitted an organism to flourish.
This is, of course, far from saying that life once existed on the red planet. I am not a biologist, but I can't help but wonder what mechanism these scientists would say played a role in producing life from nonlife on a planet having no contact with earth. As far as we know, life does not spontaneously generate from inert matter. Life doesn't simply arise when conditions are right. All the black soil in the world will not produce plants if no seeds or spores are present. If they are or once were present, where did they come from?