As soon as I saw that NASA had a "big announcement" I knew it was going to be water. It's been long theorised that Mars had water and long suspected if such is the case there would be remnants. Yay they confirmed it... I keep thinking it's not that big of a thing really...
If we could get some plant life there, like a designer fungus or something, we could theoretically create an oxygen rich atmosphere on Mars if given enough time.
I'm sure we could manage creating an algae or fungus that lives off minimal water and creates oxygen as a byproduct of existing.
It would just be super slow.
A protozoa that contains chlorophyll and produces a rich oxygen by product is more likely... I'm sure they're either searching for one, or there's one being genetically engineered.