I'll ask about that, especially if everyone there is inclined towards aqueous explanations. On the point that someone ought to be doing "gas flow modelling", that was a great link Marcia provided showing at least one team did so and found dry flows do a better job of matching the observed morphology.

Where Head seems to stand on this now is that contemporary gully formation is indeed from dry flows, but that there were "wet" gullies formed from melting H20 snow in equatorial regions during recent (i.e., last few million years) high-obliquity periods. http://news.nationalgeographic.com/news/2008/03/080319-mars-gullies.html

A couple of Head's grad students are giving talks of itnerest in the next few weeks -- one on "what CRISM findings on aqueous alteration of minerals tells us about climate in the Noachian" (more or less), and another on "dispersion of tephra from Hesperian volcanic centers". This is "summer" break for me so I may have time to make it up for those too.