beware of revisor. It has lots of issues. I tried it on an FC11 machine and it failed miserably after filling my disk with stuff that I had so much trouble finding I decided it was easier to reinstall, and I have not been that frustrated in a long time. I checked the site and it looks like it hasn't been touched in 18 months, so I think its a dead end.
On the other hand, if you pick up a copy of Linux Format this month they have a comprehensive article set on distributions that do support updated spins.
Clearly Fedora is missing the boat here. With the user base moving to virtual systems by the droves, installing a VM using a "current" Fedora spin is a huge waste of resources. Yes, you could make your own local repository to do your updates from, but again, what a waste. You've still got to move the data and process it each time.
Making a current spin with a clean set of current downloads would allow you to create an iso file that could then be used to create your virtual machines and have no downloads out of the box instead of the current requirement to bring in about 1G of "updates" just after install.
A lot of my colleagues are moving from Fedora because it's really out of control, and revisor is just another indication that Fedora is too focused on version numbers. It seems the developers have ADHD and need to move on long before they get the last version to work. That said, it's still my favorite distribution, I just wish they'd take out the trash before they start the next project.
There are a lot of other distros now that support respins and they actually work. If you make your own custom respin you can duplicate your environment wherever, whenever, and as frequently as you find useful. There are some great papers on using VirtualBox to clean up your desktop by creating small virtual machines targeted at projects which typically occupy your time.
I have found this to be very worthwhile, but most of my VM's are not based on Fedora anymore because to do an install is just too painful. (Yes, I know you can copy the vdi file if its small enough and appropriate for the next task, or even resize it, been there, done that, and its too much trouble). Custom respins of other distros install in minutes, and virtually unattended.
The following distributions support respins:
and Linux From Scratch which is a roll your own fully customized from source procedure documented in an ebook and part of Linux Formats included DVD.
Mandriva is coming along really well in this area too, but the real sleeper on the steepest polish curve is actually Debian, which was a bit of a surprise for me when I was trying all of the distributions (well top 15 anyway) to pick the one most suitable for VM replication.
Depending on what you are doing, CentOS is worth looking at. It's the stable and supported.
El Dorado Hills, CA