what does FC5 x86-64 upgrade do with i386?

[Jack Howarth]

    I am still a bit unclear on what I should expect when attempting
to upgrade a FC4 x86-64 installation to FC5 x86-64. Specifically, I
have installed the i386 firefox and associated plugin rpms on the
FC4 x86-64 machine using yum.repos.d entries of fedora.i386.repo,
fedora-updates.i386.repo and fedora-extras.i386.repo (which are all
disabled by default). How exactly does the anaconda react to the
presence of the i386 rpms on a x86-64 machine? Will they be removed
in favor of the x86-64 rpms form FC5?
    Also I have asked this several times here before but never gotten
a response. How are people keeping their i386 rpms properly updated
on a x86-64 machine? So far I can see no other option than to manually
reinstall the i386 packages with yum (using --enable-repo) when new
versions are available. However that is a very painful process and
makes it very difficult to keep the i386 rpms on a x86-64 machine
properly updated.
     Thanks in advance for any comments.
                Jack