I use a program called Beyond Compare for synchronizing various backups and folders and I’ve noticed that SharePoint  (at least for the newer versions of Excel and Powerpoint) seems to unzip and rezip these hybrid files that Microsoft uses now (.xlsx and .pptx). These files are actually zipped XML files - if you have a binary editor or simply rename a .xlsx or .pptx file to .zip you’ll see that’s how they are stored now. Anyway, the long and short of it is that when I upload to SharePoint an Excel or PowerPoint file (not sure if it happens to .docx files too yet) SharePoint unzips and rezips the contents making the files no longer identical (at least from a binary data value standpoint).
I am wondering whether the ‘new’ version of SharePoint  has this ‘feature’ too.
Asking for a friend.
(SP version numbers added in brackets by me.)
What's going on here? Is SharePoint really repackaging the Office docs? Or is it an effect of the files moving into and out of content DBs?