Curiosity has been doing its thing and impressing the masses with more Mars gossip (and hopefully keeping the public's attention long enough to actually get back some form of space program). Its latest news comes as something not many find shocking at this point, but finally put a few “theories” to bed. Mars did in fact have running water at some point in its life - the same as we have on Earth.
This all came about when Curiosity beamed back images from a dried up river bed, the stones affixed together into a layer of conglomerate rock telling as much. Shames and sizes of stones about it gave clues as to how fast the water was flowing, which was about three feet per second and was roughly ankle to hip deep in some spots.
Curiosity science co-investigator William Dietrich of the University of California at Berkeley also pointed out that there have been a ton of papers created about the canals on the Martian surface, signs of run-offs here and there, but this was the first direct evidence with measurable elements to start to uncover Mars' more liquid-rich past.
The funny thing about how exact science demands things to be: speculation with circumstantial evidence is enough to get people talking, but unless there is something more observable and measurable, it remains just that - talk. While the common person may shrug and say “yeah we've known about that, that it had oceans, has ice caps and even seen snow falling on Mars so what” it really is, for the record, a very important find and goes a long long way into better understanding the Red Planet.