Photo tagging standards, Just for my reference:
Standard photoservice tags are: "geohashing"; "geohashing(N|S)##(E|W)###" (with the graticule numbers, not zero-padded); and "geohashingYYYYMMDD" (with the date, zero-padded). Note that the word "geohashing" is used in all cases.
For example, a photo from 40,-79 on 2008-06-07 would receive the tags "geohashing", "geohashingN40W79", and "geohashing20080607". Of course, the success and utility of this method are dependent on its use by the Geohashing community.