There has been an interesting thread on the Geowanking email list about GeoChat. I too have been thinking about how we could use GeoChat with clients who don’t have ArcGIS. Maybe in time ESRI will open up GeoChat to allow others to build upon the platform. How nice would it be for a GIS Professional to collaborate with non GIS users running ArcGIS Explorer or Google Earth (heck what about any of the web-based mapping APIs)?
Of course the developer of GeoChat has a blog so any one of us could just ask him huh? ;)