A map, in a general sense of the word, is understood as a rendering or representation of a space, particularly a land area and its physical features such as roads and landmarks. A map can also refer to the spatial distribution or representation of a series of events. We could "map out" our daily routine starting from when we get up in the morning, walk to the bathroom to brush our teeth all the way to work/school and back. Emplotment is the act of sewing these routes or narratives together to create an overarching plot. 

The NomadicMilk example is great in that the project is taking the spatial knowledge of the nomadic herdsmen and transporters and showing them the rendering of the GPS data collected on the routes transporters are taking. The GPS robot’s rendering of the dairy routes illustrates the picture herdsmen and transporters have “in mind” when they think of their milk being transported, but also helps tell a larger story of the journey that dairy takes. Through this project, they are able not only to visually see the route the dairy takes but also to reflect on the journey it takes through both time and space.

Another example that helps illustrate emplotment is the mobile app SoundHound. SoundHound is primarily a music recognition and discovery app that allows users to discover new music by helping then identify songs through audio recognition or singing. But SoundHound also has an added feature where users can see what other users are "SoundHounding". Emplotment might be illustrated here if you look at the genres of music people are listening to depending on where they are. On campus, people in the library might be listening to more upbeat songs to help them focus on their homework while people in the dorms might be listening to more relaxing music to help them unwind after a long day at school. In this way, SoundHound is helping to define spatial environments by revealing what kinds of music people are listening to in those spaces. You can say that in a way this is a representation of the experiences people are having in these spaces and creates a larger narrative of the experiences those people are having on campus. The only downside to this SoundHound feature is it doesn't identify who is listening to these songs, so there is no one attributed "character" that users can follow throughout the narrative. 

The Soundhound app is intriguing - I like your ideas for drawing out some narrative from the data.  It would be interesting to take screenshots of the app in one location but at different times:  what music are people listening to on an ordinary Sunday afternoon, vs. what music are they listening to during a time of stress, such as during a hurricane warning? What are they listening to on a Saturday night?   A series of such screenshots could tell a revealing story. 

Time-space analytics beginning with Haggerstrand attempted to extend mapping of individual routes across time. It was expanded to other things and approaches. In the 19th century the maps of trade routes were joined to the incidence of cholera as it progressed globally (see my Disease Maps: Epidemics on the Ground) in a kind of "emplotment". So, simply, it's an old idea formed and reformed at different scales and for different purposes.