On the wiki page sometimes the prompt is "grub2>" , sometimes "grub>". Does it change?
A common problem (and mine) is that preupgrade didn't install the bootloader. I think this is what is dealt with by:
grub2-install <target device> --no-floppy
but a little discussion would be helpful. For instance, do you need to go through all the steps under "Encountering the dreaded Grub2 boot prompt"
For extra credit, it'd be really great to show how to install the grub2 bootloader if it's not installed, that is, if you can't get to the grub2/grub prompt.