I just updated this on a CentOS 6 box, and it broke the server. After I rebooted, it never came online. Luckily it was a backup server, so it's not critical. Right now I'm just waiting for the customer to contact iweb to figure out what went wrong. This is a vanilla server with just some of my software installed (which couldn't possibly have prevented the server from rebooting).

Obviously there is some dependency that they forgot to add, so I would hold off on updating anything unless you don't really care if the server is offline for a while.

The problem was the iweb smart layer - they just needed to recreate the smart layer.