Hi
Nice piece of history for those who are new to Fedora
http://opensource.com/life/11/7/free-sake-story-koji
"During the Core-Extras merger, being able to use Koji was a huge help
to Fedora. While some integration work was required, all other options
would have demanded much more effort. Red Hat had already been building
pre-merger versions of Core in an early version of Koji, so the
transition was simply less drastic. Furthermore, Koji's robust XML-RPC
interface allowed other parts of Fedora infrastructure to tie in with
relative ease. Over the past four years, Koji has shown its flexibility
as Fedora's needs have changed"
Rahul