It's always nice to find someone else in a completely different field who has similar interests.
When demonstrating the strength of the associations people have with each day of the week, we included data from lab-based experiments, Google search and Ngram enquires. As with our experimental data for example, Google searches found fewer occurrences of midweek days in webpages and books (see below).
However, we didn't include data from Twitter and last week a colleague spotted the recent work of Jeff Sisson. Have a look here.
His page automatically counts the number of times people on Twitter say something like "today feels like a ___" for any given day of the week. It even stores the resulting data. Remarkably, the results so far are almost identical to our own, but it is also possible the analyse these effects across the week...which I will post below in due course.