I was going to use SME server on the data cluster becuase thats what the web and email servers have on them. I didn't want to intermingle linux version in one environment for one task: serving up a highly data driven website and email for a few thousand people.
and the real time requirement is from the client, not me. i flat out told them that doing stuff in real time at a minimum increases hardware costs 6 times.
also, i have a SME 7.X VM running my personal web site running on a server in my house. I thought it was pretty slick. Then again, i get maybe 1 visitor a day. oddly enough, i have the VM down while building two development environments for my employer (from a dd) ... plus win2k3 is running, plus 3 product testing simulations.... VMware server can bring even the most hearty servers to their knees and get for mercy. I wont be using VMs for this client though.
so, CentOS 5 is more up the the task(s) i described? I will build a VM and see if there are any major or minor administration differences. although very off topic, both SME and CentOS support webmin, right?