It has been known that Mars has water, the question is how much. I don't know how deep below Mars' surface Odyssey's instruments can peer.
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"A few meters" Your intepretation of this may vary. :)
Note that mission scientists characterized the hydrogen signal as very strong. The apparent fact that there is most probably accessable water (within a few meters of the surface) over most of Mars does shed a very different light on possible long range missions there.

I still favor the idea of crewed missions to NEOs as a logical, scientifically rewarding and affordable next step in the human space flight arena.

-p