The Penn State researchers define the activity of geocollaboration as a group working together to solve geographic problems facilitated by geospatial information technologies. Others view geocollaboration as any form of collaboration that involves geospatial data.
One level of collaboration in a geospatial context involves sharing of data and/or applications by and among various organizations. This level of geocollaboration is at the less interactive, open community end of the spectrum and illustrates the trend toward increased awareness of the need for better geocollaboration capabilities.
An example of a collaborative GIS tool that has been developed to support multi-agency cooperative work with geospatial data is the Geospatial One-Stop. It uses the approach of providing portals or channels to various web sites that support sharing of geospatial data and applications.
Even though it's more focused on geo-groupware, there's a lot to learn from this field.