About Mars, it has water frozen at the poles we know that already, the temperature on mars differenties between 80F (high summer) and -200F (at the poles during winter)
mars Sidereal day (meaning the time it turns 360 degrees) is 24 hours 37 minutes and 22 seconds making it a suitable place to live if we could get oxygen into its atmosphere, the oxygen itself will need to be taken from the planet itself. (the frozen carbon dioxide at the poles are highly interesting)

the downside to live on mars in the future is its lack of a magnetic field wich protects our own planet from alot of cosmic radiation, especially the high energy particles hurled into space during a solar flare.

but as bentherdonethat said its a milestone in our venturing out into space. although traveling through space is tricky due to the immense distances we need to overcome if we would like to visit our nearest star (other than the sun) wich is alpha centauri and the distance to that our closes star neighbour is 4.37 light years. wich speaks abit about finding another planet to live on.

i say who cares about water.. we need to find life...

they know there are planets that out there already, that they have images of that are 100% ocean.

Where theres water theres life.