Today's Image of Mars is is a color mosaic of the "Kirkland Lake" boulder field, as compiled and colored by The Road to Endeavour's Stuart Atkinson from images taken by Mars Exploration Rover Opportunity.
Opportunity is now leaving all this behind as the MER team directs it toward the location of the low-acidic clays detected by CRISM and HiRISE in orbit. The MER team is hoping that these clays can tell them more about how hospitable Mars was in the past.
This image links to the larger, amazing version from The Road to Endeavour, but the post in which the image is found is here. The small photo below really doesn't do the image justice because the original is extremely detailed.