Both seem uncertain of reaching weight, and seem to have similar goals and overlaps. I understand many of the top users of each may not be terribly interested in the topics of others, but each may have some points to contribute to questions on the others. If they appear likely for failure, would a combined Geography & Cartography effort have a better potential? Have found Earth Sciences SE has very slow activity despite combining fairly disparate fields of geology and meteorology. Yet each helps the other to keep going, and make a fairly useful site. Would seem to be best here as well?