[CentOS] Completely automatic yum updating on Centos 6

From: Frank Cox <theatre at melvilletheatre.com>

> I am about to set up a computer with Centos 6 that I'll probably never see
> again.  I don't want to give out the root password, but I would like to have 
> it automatically and transparently update itself.

What about .rpmsave and .rpmnew files...?
How long does the apps support the old configurations files formats...?

JD