Guys, with all respect, I'd be happy to see you rethink and rewrite the XF upgrade process and streamline it for a less painful experience. The downloading of a zip file, uploading it to the server, unzipping, copying files and then redoing it all over again just to make the upgrade process work makes this all feel old fashioned and broken. Vulnerable web apps is a major security issue in the web, and that asks for an easy streamlined upgrade process for the apps. XF does not have it.
For a comparison and a reference implementation, I yesterday updated my server's Webmin app. The app showed me a message that there's an update available and a button next to it to start the upgrade. Hitting the button was all it took, nothing else. The app updated and that's all. No manual downloading, uploading, copying or anything, just a single hit on the upgrade button. Please make it as easy and streamlined for XF!