New approaches are needed to think about audiences, subcultures, and publics in the context of increasing attention to the pluralistic nature of modern societies. Subgroup differences influencing reactions to technological change abound but may not correspond neatly to national boundaries. Often attributed to the influence of media messages, these differences are more clearly associated with message interpretation than with uniform media effects. In other words, reactions are better understood as a function of what audiences bring to the interpretation of news and information than as a function of exposure to message content itself. As an example, this article considers persistent differences between the US and Canada in opinions about technology that can be traced through comparative survey data collected by the Canadian government in 2003, 2004 and 2005. Previous research by the author has suggested, based on the data from the 2004 survey, that these differences can be accounted for by differential distributions within each country of subgroups with different perspectives on the inherent value of science, on whether decisions in this area should be driven by ethics or by utilitarian concerns, and on who should make those decisions. Here, comparative Canada-US survey data from January 2005 are used to explore explanations based on media consumption, source credibility, and perceived social distance (from developers) characteristic of these groups, as well as to extend the analysis from biotechnology to nanotechnology as well. Theoretical and practical implications are discussed.