I was cleaning up my system getting rid of winxp (I had it on a separate hard drive) and deleted all of the stuff associate with it. I copied off all that I wanted and I was going to reformat the drive to add the space to my Fedora volgroup. I used gparted to delete the partitions. I got the message I had to reboot to clean up residual pointers. I rebooted and I lost grub2. I then remembered I had put grub2 in the mbr of that hard drive. After spending hours trying to get every thing back and failing, I decided that the only may was to re-install Fedora and hope my data was saved. I loaded the FC16 DVD and started to upgrade my system. To my surprise, the instal process rebuilt a good grub2 configuration and, because I have kept up with the fixes and updates to Fedora, no software was reloaded. Bottom line - next time I screw up grub2 (not very likely from now on) I will just go through the install and let it rebuild my grub2 configuration.
I hope this save someone else some time when they lose grub2.