I found Steve's original post on diplomacy changes and treaties, but wasn't able to find the information I'm looking for.
One of my NPRs granted me a geosurvey sharing treaty. How does that work? Am I supposed to see their galactic map now, with all the systems/planets they've surveyed? If I reciprocate, does the NPR see my entire map? Or when I jump into a system they have surveyed, do I see that their planets have been surveyed?