Thanks for the link, Alex. It seems like another line of "not proof of Martian life, though not disproof, either".

In their conclusions, the authors state: "The technology needed to address the question of the detailed shapes of nanocrystals, and the proposed similarity between magnetite crystals from bacteria and the ALH84001 meteorite, is available. The problem could be solved by using one or more of the methods mentioned above for measuring the projected thicknesses of crystals to reconstruct their three-dimensional morphologies. In this way, a more definitive and unambiguous study could be performed than has been carried out to date. Such measurements also could be made on the products of experiments that indicate magnetite crystals similar to those from ALH84001 have been grown inorganically (29). Because it seems that the magnetite nanocrystals in ALH84001 are the only remaining, potentially definitive indicators of former life on Mars, such careful work is justified and, indeed, demanded. "

Do you know if anyone is doing or planning such work?

I maintain the opinion that, though no single piece of evidence for past life on Mars is conclusive, that the sum of them all is compelling. It seems as if the naysayers tune is "Point 1 can be explained non-biologically by conditions a, b, and c; point 2 can be explained non-biologically by conditions d, e, and f; etc".

IMVHO there don't seem to be any all-encompassing explanations for all the points of evidence, other than life.

Hopefully Odyssey will continue to add pieces to the puzzle solution.