Hi,
run your yum update with -d7 and pastebin.ca the output ( make sure to set expire to never or > 7 days), and pastebin the url here. make sure you include _ALL_ of the yum output not just snippets of it.
Don't know what pastebin.ca is. Did not find that on this machine. So I'm attaching yum output here.
afaict, you have something broken on your setup, or an exclude or plugin is causing issues there.
AFAIK I have no excludes and disabled all plugins.
Andreas