repoman currently has no support for yum repos at all. When it gets a URL as a package source, repoman currently first attempts to detect if that URL is a Jenkins job, and if not, it just tries to download the artefact directly from the URL. To use a yum repo with repoman, one need to explicitly specify the 'rec:' flag, to make it search for artifacts recursively.
Full yum support in repoman can have many features, such as reading the yum metadata files to figure out which packages are in the repo, and preforming version calculations prior to downloading packages. This ticket is not about that.
This ticket suggests a simpler implementation to make repoman "aware" of yum repos to make it slightly easier to use and reduce user surprise while full yum support is being developed.
It is suggested that when receiving a source URL, repoman will check for a '*/repodata/repomd.xml' file in a similar fashion to the way it checks for the Jenkins API, and if found will act as if the 'rec:' flag was specified.