The research on technology for emergency management is usually based either on studies in the field that focus on workers using current tools or on the development, testing, and deployment of novel software tools used in controlled settings. Little is known about the effects of the new collaborative media and work conditions 'in comparison to' the current media and conditions. In 2007, we presented at ISCRAM a method for studying common ground development through a paper prototype in face-to-face collaboration and subsequently presented preliminary findings on common ground development. In this paper we present preliminary findings from an analogous experiment on teams working remotely via a geo-collaborative software prototype. We compare these findings with those from the prior paper prototype study. We use this comparative research design to explore implications for system design and theory development in computer-supported cooperative work.