This plugin will use delta-rpms in any presto-ready repository.
You don't need to touch anything.
PS: I'm sorry. Taking a second look, I found the following change in /etc/yum.repos.d/fedora-updates.repo:
Code:
[updates]
name=Fedora $releasever - $basearch - Updates
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/updates/$releasever/$basearch/
deltaurl=http://lesloueizeh.com/f7/i386/updates
mirrorlist=http://mirrors.fedoraproject.org/mirrorlist?repo=updates-released-f$releasever&arch=$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora
...
The add is the deltaurl entry.