GRUB with Ext4 Support
Fedora 9 originally included experimental support for Ext4 and Fedora 11 included Ext4 by default however GRUB in that version did not support Ext4 and hence required a separate boot partition formatted as Ext3 or Ext2. Fedora 12 now includes a updated version of GRUB with Ext4 support. Anaconda, the Fedora installer will permit this as well.
Dracut - New Booting System
Up until Fedora 10, the boot system (initial ram disk or initrd) used to boot Fedora was monolithic, very distribution specific and didn't provide much flexibility. This will be replaced with Dracut, a initial ram disk with a event based framework designed to be distribution independent. It has been also adopted by the Fedora derived OLPC project's XO operating system. OLPC modules for Dracut is available in the Fedora repository. Early feedback and testing is welcome.
Faster and Smoother Graphical Startup
Kernel Mode Setting (KMS) is now enabled by default on Nvidia systems as well through the Nouveau driver. Fedora 10 originally included support for KMS but only for some ATI display cards. In Fedora 11, this was extended to Intel cards as well. This release has extended it further to support Nvidia cards as well.
As as result of this improvement, you will get a faster and smoother graphical boot on (nearly) all systems via the Plymouth graphical boot system developed within Fedora.