Upgrade to Fedora 13 from your existing version using yum.

Well. this time it seems to be very simple :

yum –releasever=13 upgrade

update 22/April/2010:
The key file will not be there so there are two options for you in this case:
1) Install the following rpms from the downloaded rpms with \”yum –nogpg localinstall\”
a) fedora-release
b) fedora-release-notes
2) Run the whole upgrade with –nogpg option.

Issue observed after the upgrade:
The new kernel was not added in the grub menu and I had to manually add the below entry in the menu.lst file:

title Fedora (
root (hd0,11)
kernel /boot/vmlinuz- ro root=UUID=f832d6ce-dad3-4af9-9ef1-aac950f8284c rhgb quiet SYSFONT=latarcyrheb-sun16 LANG=en_US.UTF-8 KEYTABLE=us init=/sbin/bootchartd

Because of this I was not able to start the X server until I restarted the system with the entry in place and selecting this in the GRUB menu.