How does the "White Mars" hypothesis fit in with these?
Earth-like planets probably water-logged
http://www.nature.com/nsu/030818/030818-10.html
SURFACE WATER POSSIBLE UNDER MARS-LIKE CONDITIONS
FAYETTEVILLE, Ark. — A team of researchers from the University of Arkansas has measured water evaporation rates under Mars-like conditions, and their findings favor the presence of surface water on the planet. Water on the planet’s surface makes the existence of past or present life on Mars a little more likely, according to the group.
http://advancement.uark.edu/news/SEP03/sears.html