Let's try the easy way - PreUpgrade!
First potential problem, after the first reboot - nothing happens. We boot into normal Fedora 14.
Edit the grub.cfg or grub.conf to default to:
title Fedora install
kernel /boot/upgrade/vmlinuz-install ro root=LABEL=/ rhgb quiet
Now reboot to continue the upgrade process.
Next problem, Fedora 15 boots in wrong screen resolution.
After fixing grub.conf again, we can't find the shutdown/restart button. I had to turn off the power. The hidden button is the suspend button with alt pressed. After reboot we now have to deal with Gnome3. Do they think I am blind, that I need a menu that takes over my whole screen? blocking out anything that was being displayed?
Quick go to fallback mode and get some semblance of a workable desktop back. System Settings->System Info->Graphics->Forced Fallback Mode.
Run this to get yum working again:
rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-rawhide.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-rawhide.noarch.rpm
Now I am trying to edit the menus, alacarte's submenus no longer work!