When you updated, it probably updated the kernel to the latest version. When you update the kernel, the old one is retained in case something goes wrong with the new one.
The location of the OS titles in grub is /etc/grub.conf . In here, you'll see something like this:
Code:
title Other
rootnoverify (hd0,0)
chainloader +1
Change 'Other' to whatever you want and save the changes.
To remove an old kernel version after you've installed a new one and verified that it works, use (as root)
rpm -e kernel-<version>
Since you're already in grub.conf, look at the 'title' parameter for the old kernel version, which should say something like 'Fedora Core (2.6.11-1.14_FC3)'. The version number will be different for you, but you get the idea. In this case though, you'd say 'rpm -e kernel-2.6.11-1.14_FC3'.