"mod_pagespeed and ngx_pagespeed are officially in Apache incubation as "Apache PageSpeed".
The official discussion forum moved over to:"
Where are the sources of the project now? Because the Google binaries repository http://dl.google.com/linux/mod-pagespeed/deb/ doesn't seem to be maintained anymore. There are GPG signature errors:
Ign:5 http://dl.google.com/linux/mod-pagespeed/deb stable Release.gpg Reading package lists... Done W: GPG error: http://dl.google.com/linux/mod-pagespeed/deb stable Release: The following signatures were invalid: EXPKEYSIG 78BD65473CB3BD13 Google Inc. (Linux Packages Signing Authority) <linux-packages-keymaster@google .com> E: The repository 'http://dl.google.com/linux/mod-pagespeed/deb stable Release' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.