Updating this post a little for those not following who want the basics.
Picture of ice dug under the top soil of mars disappearing over a period of 4 days by sublimating (Definition:
Sublimation of an element or compound is a transition from the solid to gas phase with no intermediate liquid stage).

Dirt load delivered to wet chemistry lab.

Optical Microscope sample of dirt from mars showing particles.

Concerning the analysis of the soil sample.
QuoteWe basically have found what appears to be the requirements, the nutrients, to support life whether past present or future," Sam Kounaves, the lead investigator for the wet chemistry laboratory on Phoenix, told journalists.
"It is the type of soil you would probably have in your back yard, you know, alkaline. You might be able to grow asparagus in it really well. ... It is very exciting for us."
The 1 cubic meter (35 cubic feet) of soil was taken from about 1 inch below the surface of Mars and had a pH, or alkaline, level of 8 or 9. "We were all flabbergasted at the data we got back," Kounaves said.
Quote from http://www.reuters.com/article/scienceNews/idUSN2634952620080626
Well that is some of the latest info, since last post.