Water on the surface of Mars?

Maybe. [Link]

So far, the best explanation for all this involves flowing, liquid water. It's too cold on Mars for fresh water to remain liquid, but if the water was salty (about as salty as ocean water here on Earth), it would lower the freezing point enough that during the Martian summer, a briny liquid could flow at or very near the surface of sun-warmed slopes. You'd get the highest flow rates during the summer, and then the water would refreeze during the winter, which seems to be what the imagery shows.
As exciting at this discovery is, there are still lots of questions that need to be answered. Where this water actually comes from is an important one that could influence future target sites for future unmanned or manned Martian missions. And of course, there's the potential for life: here on Earth, briny water makes a great habitat for microbes. Ultimately, these new images may spawn a whole new series of riddles, but that's just part of the charm of Mars: far from being a dead and dusty planet, it's turning out to be a dynamic world with an evolving surface that may provide insights to the processes that have shaped our own Earth.