"There's no greater mystery than a mystery cropping up somewhere you thought you understood. In the case of the Martian plain Hesperia Planum, it was filed under "Region on Mars. Not Particularly Interesting. No Further Study Needed."
... But if water is a possibility, then Hesperia Planum suddenly became a lot more interesting. Evidence for a watery past plus ancient volcanism may have provided the ideal environment to incubate life."
- Discovery News, via "The Mystery of Mar's Bizarre Plumbing" - 10/13/2011 - Ian O'Neill
Yet another newly reevaluated area - Hesperia Planum - which poses the possibility of past life on Mars!
(Found today on Graham Hancock's News Page.)
And another Discovery article from March of this year that I somehow missed: