A little bit of background first:

The Workstation images include a package called PackageKit-cached-metadata that ships a snapshot of yum repo metadata. This was done in order to make gnome-software initial experience better, so that it wouldn't have to go and download a huge amount of metadata just to be able to show what's currently installed in the system.

Normally, it's fine if the cached metadata package is a little bit behind, as gnome-software refreshes the metadata daily. 

However, this approach had some downsides. First, we normally don't keep the package up to date and only update it before the release. This means that during pre-release testing it is sometimes horribly out of date.

Secondly, shipping it in a subpackage of PackageKit means that whenever PackageKit is updated, post-GA, users also have to download a 100 MB cached metadata package update.

Third, the manual updating is time consuming to do manually and error prone. For example, last release we accidentally shipped x86_64 cached metadata for i686 images ...

These reports all stem from the fact that PackageKit-cached-metadata is out of date:

https://lists.fedoraproject.org/pipermail/test/2015-October/128127.html
https://bugzilla.redhat.com/show_bug.cgi?id=1264632
https://bugzilla.gnome.org/show_bug.cgi?id=755819

So, I talked to dgilmore about this today and we came up with a better solution, which is to automatically copy the metadata over from https://kojipkgs.fedoraproject.org/mash/ during image composes. I came up with a spin-kickstarts change, http://paste.fedoraproject.org/281027 that implements this. I would like to switch to the new approach for next TC/RC; as far as my testing goes, it's working as expected and much better than the previous approach. This change would involve:

1) applying http://paste.fedoraproject.org/281027 to spin-kickstarts
2) dropping PackageKit-cached-metadata from comps
3) doing a new PackageKit build that obsoletes and drops the PackageKit-cached-metadata subpackage

A test image that dgilmore built with the patch above is available at http://koji.fedoraproject.org/koji/taskinfo?taskID=11501773 if anyone wants to try booting it and seeing if gnome-software works.