James Head is a highly regarded planetary geologist. His giving this idea serious consideration leads me to believe most Mars scientists will now also consider it to be a legitimate possibility.
Note he is not saying such glaciers are currently active. He is ascribing it to a former period of high obliquity.
However he is apparently supportive of the idea that there is relict ice still there that stems from this period:

Earth-based Analogs of Mars Offer Insight into the Red Planet.
"A huge cache of water ice once existed at Arsia Mons, Head speculates. High-resolution pictures of the area, as well as laser scan data of the terrain, both relayed from the Mars Global Surveyor, support the idea that ancient ice may still exist there. This working hypothesis builds upon earlier work of Mars researchers David H. Scott and James Zimbelman, he acknowledged."

Note that the JGR paper discussing the high water vapor amounts over Thasis was co-authored by Steve Clifford, one of the most highly regarded Mars hydrologists.
Note that Clifford has proposed a model to explain how ice could persist in near equatorial regions long term on Mars:

Title: A model for the hydrologic and climatic behavior of water on Mars
Authors: Clifford, S. M.
Journal: Journal of Geophysical Research, vol. 98, no. E6, p. 10,973-11,016.
http://adsabs.harvard.edu/cgi-bin/bib_query?1993JGR....9810973C [Abstract]

Quite key here is that Clifford did not propose this idea arbitrarily. He was led to this conclusion from studies of "splosh" craters that suggested there was recent water/ice near surface in the equatorial regions of Mars:

Splosh Craters: Evidence for the Replenishment of Ground Ice in the
Equatorial Region of Mars
http://adsabs.harvard.edu/cgi-bin/bib_query?1982LPI....13..121C [Full text]

Mars: Ground Ice Replenishment from a Subpermafrost Groundwater System
http://adsabs.harvard.edu/cgi-bin/bib_query?1981LPI....12..157C [Full text]

The Huguenin and Clifford JGR paper suggested the anomalous water vapor amounts seen over Tharsis stemmed from seasonal melting of regions they contend contained near surfacce *liquid* water. However, because of the diurnal variations of the water vapor over Tharsis another possibility is that it stems from diurnal exchange with the regolith from ice in Tharsis itself:

Title: Ice hazes and clouds in the Martian atmosphere as derived from the Phobos/KRFM data
Authors: Petrova, E.; Keller, H. U.; Markiewicz, W. J.; Thomas, N.; Wuttke, M. W.
Journal: Planetary and Space Science, v. 44, p. 1163-1176.
http://adsabs.harvard.edu/cgi-bin/bib_query?1996P&SS...44.1163P [Abstract]

Note these are several separate and INDEPENDENT indications for the conclusion that near surface water/ice currently exists near the equator on Mars.

Bob Clark