The first thing I did was try and update OpenSSH, as per the example, but I ran into a problem right away. It said that the files were "not provided," and got stuck updating out of a dependency loop. This turned out to be a bug already logged into Bugzilla, only for OpenSSH. Turns out it's also not working for Mozilla, vncserver, and a few others. Worked for gaim, though. And vncserver worked as "install," instead of "update." Hmm... The workaround was "yum update" (no package listed) which updates ALL packages. That seemed to work very well on both 7.3 and 9.0.
But the second 9.0 box it totally got looped into "rpm hell," which by its very nature, is kind of ironic. First yum needed libxml2-python, which in turn needed libxml2, which needed libpthread.so.0 which needed glibc 2.3.2... which wouldn't install because it said it was in conflict with another glibc version. Bummer. Since I didn't want to hose this box, I gave up.
I think if you have the right stuff preinstalled (like python), yum is a great way to update your box without going through up2date. But if you have a specialized box with some stuff removed, you might as well just use up2date. I suspect this is a project in the works, so I will be anticipating further releases