I think they’re onto something, but I’m not sure that I understand it in the same way they do. I believe they’re really looking at how the mind integrates various experiences into a “useful” unified strategy for communication. People solidify their thinking about how to use a medium when they are young. (You and I learned to use telephones and written letters. In college we used BBS’ and early email systems, like Plato-IV in my case.) Then later on as new media become available, they have to cross the boundaries and figure out how to integrate those media. In a sense they become “trans” literate as they go thru this process. Sue and researchers associated with her are trying to understand how these things happen and develop vocabulary to talk about the media, the media events, their utilization and how they fit into the users’ lives.