Differences between fc3 repositories

[Kitano]

Someone know about the kind of differences between download.fedora.us
and download.fedora.redhat.com?
I'm trying to configure up2date and apt to work together and both have
the same repositories. Although I'm in troubles because I can't find
apt repositories for download.fedora.redhat.com and neither yum
repositories for download.fedora.us.
In the case that is not possible to have the same repositories in both
files I want to know if the two repositories are properly synchronized
and if they contain the same packages.

Any suggestion is well received ;)