From article:

"Caltech’s Oded Aharonson and colleagues, for example, suggest that the streaks mark places where the sun warms up water ice enough to melt it for a short while. Team members presented their own update on the dark-streak mystery at the AGU meeting — sparking a debate on the Habitable Zone’s message board.
Yet another view, put forward by Malin Space Science Systems’ Kenneth Edgett and colleagues, holds that the streaks are most likely caused not by water, but by avalanches of dry dust.
“There really are, at this point, three different stories,” Edgett said.
“The problem with the business is that we have all these pictures, and it’s very common that people will look at a picture and say, ‘Oh, I know what that is,’ and go off and model the process,” he said. The challenge, however, is to explain what it is about the land form that backs up your interpretation.
“I have a tough time seeing what it is about this land form that would give me any indication one way or another that would have anything to do with water and ice,” Edgett said.
The U.S. Geological Survey’s Justin Ferris, who was a part of the Arizona team, acknowledged that no one has yet found the smoking gun in this Martian mystery.
“There is no identifiable characteristic of a dark slope streak that can definitively say whether it was formed by water-related processes or not,” he said. “But there are certainly some features which strongly suggest the role of water.”

If they are liquid water related perhaps they are modeled by the dark streaks seen on slopes in the dry valleys in Antarctica, due to freeze-thaw cycling. There are images of such dark streaks on Antarctica slopes that have the appearance of the Mars dark streaks:

From: "bobbygc2001" <bobbygc2001@y...>
Date: Sun Jun 30, 2002 6:23 pm
Subject: Re: New report supports England/Palermo that the "dark streaks" are water related.
http://groups.yahoo.com/group/cydonia/message/17340

This is in fact the model originally proposed by Ferguson and Lucchitta:

Dark streaks on talus slopes, Mars
In NASA. Washington Rept. of Planetary Geol. Programs p 188-190 (SEE
N84-23431 13-91)
http://adsabs.harvard.edu/cgi-bin/bib_query?1984pggp.rept..188F
[abstract]

Bob Clark