.csv files are getting an "application/vnd.ms-excel" mimetype and are not triggering the text/csv extractor (they do if the mimetype is changed to text/csv).
"application/vnd.ms-excel" appear to be generic to several file types, but at least .xlsx is getting a different mimetype in my test.

Teh goal is to get csv files extracted when they're uploaded with what appears to be a default mimetype coming from windows machines...