They’ll be PreVeiW files – maybe like thumbnails. Probably some setting somewhere…..
Part of Portfolio Saved View (Extensis),
"Saved Views (PVW files) can be used to import/export ‘saved views’ of Galleries. These files hold the Gallery’s customisations except for the information on the Saved Options tab, but only for their host OS. In order for view settings for both OSs to be captured, the customisations must be set via the Catalogue running on each OS in turn before the PVW file is (re-)saved." blah, blah, blah….