*Optimized performance - All software packages on 32-bit (x86_32) architecture have been compiled for i686 systems, with special optimization for the Intel Atom processors used in many netbooks, but without losing compatibility with the overwhelming majority of CPUs.
* Smaller and faster updates - In Fedora 11, the optional yum-presto plugin, developed by Fedora contributor Jonathan Dieter, reduced update size by transmitting only the changes in the updated packages. Now, the plugin is installed by default. Also, RPMs now use XZ rather than gzip for compression, providing smaller package sizes without the memory and CPU penalties associated with bzip2.
* NetworkManager broadband and other enhancements - NetworkManager, originally developed by Red Hat's Dan Williams, was introduced in Fedora 7 and has become the de facto network configuration solution for distributions everywhere. Bluetooth PAN support offers a simple click through process to access the Internet from your mobile phone. NetworkManager can now configure always-on and static address connections directly from the desktop. PolicyKit integration has been added so configuration management can be done via central policy where needed. IPv6 support has also been improved.
* Next-generation (Ogg) Theora video - For several years, Theora, the open and free format not encumbered by known patents has provided a way for freedom-loving users to share video. Fedora 12 includes the new Theora 1.1, which achieves very high quality comparable to H.264, meeting the expectations of demanding users with crisp, vibrant media in both streaming and downloadable form. Theora videos now deliver much better quality primarily via enhancements in the encoder without any change in the format, making it available to all Theora users.
* Graphics support improvements - Fedora 12 introduces experimental 3D support for AMD Radeon HD 2400 and later graphics cards. Kernel mode setting (KMS) support, which was introduced on AMD hardware in Fedora 10 and extended to Intel hardware in Fedora 11, is now extended to NVIDIA hardware as well, meaning the great majority of systems now benefit from the smooth, fully-graphical startup sequence made possible by KMS. The Fedora graphical startup sequence now works better on systems with multiple monitors. Also on multiple monitor systems, the desktop will now automatically be spread across all monitors by default, rather than having all monitors display the same output, including on NVIDIA chips (where multiple monitor spanning was not possible without manual configuration changes in Fedora 11). Systems with NVIDIA graphics chips also gain initial support for suspend and resume functionality via the default Nouveau driver. driver for NVIDIA).
* Virtualization improvements - Not content with all the improvements in Fedora 11, we've kicked virtualization based on KVM up another notch in Fedora 12. There are extensive improvements in performance, management, and resource sharing, and still more security enhancements. A new library (libguestfs) and an interactive tool (guestfish) are now available for directly accessing and modifying virtual machine disk images.
* Automatic reporting of crashes and SELinux issues - Abrt, a tool to help non-power users report crashes to Bugzilla with a few mouse clicks, is now enabled by default. Abrt collects detailed information automatically and helps developers identify and resolve issues faster, improving the quality of individual upstream components and Fedora. The SELinux alert monitoring tool has also added the ability to report SELinux issues to Bugzilla quickly and easily with just a couple of clicks.
* New Dracut initrd generation tool - Up until Fedora 11, the boot system (initial ram disk or initrd) used to boot Fedora was monolithic, very distribution specific, and didn't provide much flexibility. This has been replaced with Dracut, an initial ram disk generation tool with an event-based framework designed to be distribution-independent.
* PackageKit plugins - PackageKit now has a plugin which can install an appropriate package when a user tries to run a command from a missing package.
* Bluetooth on-demand - Bluetooth services are automatically started when needed and stopped 30 seconds after last device use, reducing initial startup time and resource use when Bluetooth is not in active use.
* Moblin graphical interface for netbooks - In additional to special compiler optimization for netbooks in this release and the continued integration of Sugar interface, the Moblin graphical interface and applications are fully integrated.
* PulseAudio enhancements - Red Hat's Lennart Poettering and several others have made significant improvements to the PulseAudio system. Improved mixer logic makes volume control more fine-grained and reliable. Integration with the Rygel UPnP media server means you can stream audio directly from your system to any UPnP / DLNA client, such as a Playstation 3. Hotplug support has been made more intelligent, so if you configure a device as the default output for a stream, unplug that device -- causing the stream(s) to be moved to another output device -- and later reattach it, the stream is moved back to the preferred device.
* Lower process privileges - In order to mitigate the impact of security vulnerabilities, permissions have been hardened for many files and system directories. Also, process privileges have been lowered for a number of core components that require super user privileges.
* SELinux sandbox - It is now possible to confine applications' access to the system and run them in a secure sandbox that takes advantage of the sophisticated capabilities of SELinux.
* Open Broadcom firmware - The openfwwf open source Broadcom firmware is included by default. This means wireless networking will be available out of the box on some Broadcom chipsets.
* Hybrid live images - The Live images provided in this release can be directly imaged onto a USB stick using dd (or any equivalent tool) to create bootable Live USB keys.
* Better webcam support - While Fedora 11 improved webcam support, in Fedora 12 you can expect even better video quality, especially for less expensive webcams.
* Polished Desktop - The latest version of the GNOME desktop includes the lighter Gnote replacement for Tomboy as the default note application, and Empathy replaces Pidgin as the default instant messenger. The new volume control application, first seen in Fedora 11, has been improved to cover more advanced users.
* GNOME Shell preview - Fedora 12 includes an early version of GNOME Shell, which will become the default interface for GNOME 3.0 and beyond. This is a preview technology, and some video cards may not be supported.
* KDE 4.3 - The new KDE features an updated "Air" theme and fully configurable keyboard shortcuts in Plasma, improved performance and new desktop effects in the window manager, a new bug reporting tool, and a configuration tool for the LIRC infra-red remote control system.
* Multi-Pointer X - The update to X.Org server 1.7 introduces the X Input Extension version 2.0 (XI2), with much work contributed by Red Hat's Peter Hutterer. This extension provides a new client API for handling input devices and also Multi-Pointer X (MPX) functionality. MPX functionality allows X to cope with many inputs of arbitrary types simultaneously, a prerequisite for (among others) multitouch-based desktops and multi-user interaction on a single screen.