No observations of liquid water yet but the surface has not been completely mapped by THEMIS yet.
The Malin/Edgett gullies are within the resolution range of the visual imager on THEMIS. So if we see new gullies in an area where prior MGS images showed none then we have a likely case for liquid water.
As for evaporites there was this article in Nature about bright white deposits which had the appearance of sulfates:

Surveyor spacecraft spots bright sand dunes on Mars that researchers speculate could be mounds of sulfates
FOR RELEASE: Feb. 17, 1999
http://www.news.cornell.edu/releases/Feb99/thomas.mars.deb.html

The size of these deposits should be within the range of the THEMIS infrared imager. It is also possible these deposits could be carbonates.
Remember also the images of the sedimentary layers wide spread at the equator on Mars? Several images had spotty white deposits that might also have been sulfates or carbonates.
Finally I would to see settled once and for what is the true color of White Rock.

Bob Clark