press F4 on the first screen and select "Install a minimal virtual machine"
If JeOS (Just enough OS) only runs in virtualization, I'd tend to think of it more as NeOS.
How about Xubuntu? I've set that up in QEMU vitual images, and it runs a lot faster than Ubuntu. Oh, wait, I see. It's for farms of VMWare images. Ever mind.
Ah how timely I was just going to install Ubuntu on Vmware.
Minimal ubuntu includes gnome? That is way overkill.
JeOS itself does not even include an X server. It's designed for farms of virtual machines. I think it would be a slick platform to run on ec2 but Amazon supplies their own kernel images. My guess is that the article poster just wants a small Ubuntu to run on their local box, but doesn't feel comfortable using a pure command-line interface.