Release notes:

GUI:

• Improved XBMC GUI Skinning Framework making it even more flexible and powerful
• Powerbutton follows “shutdown function” in settings/system/power saving
• Updated translations for most languages (help is always wanted with translation)
• Skinnable Weather Plugin API enabling third-party Weather Plugins (Python Scripts)
• Edit button for RSS feeds in settings, (needs RssTicker script installed, see SCRIPTS section below)
• New screensaver option to turn off the screen (using VESA DPMS)
• Always On Top option to advancedsettings.xml when XBMC runs in Windowed Mode
• Better support for multi-monitor setups
• Settings have been re-organized and cleaned up to sync with new features

Playback:

• High Definition, Surround Sound, and Subtitle Flagging and Filtering in Video Library
• Added support for SingStar and UltraStar Karaoke Lyrics Format
• Updated FFmpeg (libavformat and libavcodec) audio/video codec and demux library
• Speed up RAW image loading and handle more file extensions
• Implemented better WAV/PCM handling on 64-bit operating-systems
• Added support for additional tags in CUE sheets (Genre/Year)
• Added support for MPL2 (Blu-ray) subtitles format
• Added support forVPlayer subtitles format (which unfortunately is still in use)
• Added support for RTMP (Flash) live video streams, plus skip, pause, and resume feature
• Added proper MMS/MMSH streaming client (libmms) support
• Added audio and subtitle delay pop-up to the GUI (similar to volume control)
• Improved Commercial Skipping, EDL (Edit Decision List), and SceneMarker support
• Options for smoother video playback (syncing the video to the refresh rate of the display)
• Smart Playlists support for video resolution, aspect-ratio, codec, audio, and subtitles
• Extension of ExternalPlayer enabling multiple external players based on file-extension
• Added overlay renderer for dvd/vobsub/xsub

Library:

• Performance improvements to SQLite (database) queries (help is always wanted here)
• Support for movie sets and a sortorder tag in the Video Library
• UPnP MediaServer compliant with DLNA (Digital Living Network Alliance) standards
• Ability to view pictures over UPnP in XBMC, also loads of fixes to the UPnP library
• Added scan for new content command to HTTP API, extended XBMC.updatelibrary call
• Reorganized MythTV directory structure to separate TV Shows from Movies
• Support importing MythTV movies into the Movies Library (including scraping)
• Added support local actor thumbnails (store as actor_name.tbn under .actors directory)
• Scrape studio info for TV Show/Season/Episode, info is available via studio field item
• Changed handling in Scrapers and NFO replacing «thumbs» with multiple «thumb»
• Added library update on resume if we are coming from suspend/hibernate
• Ability to scrape and scan TV Shows into the video library by air-date via TheTVDB.com

Scrapers:

• TheMovieDB.org (TMDB) movie scraper upgraded to version 2.1
• Added Movie Trailer scraping from dtrailer.com to TheMovieDB.org scraper
• TheTVDB.com TV Shows scraper scraper improvements and enhancements
• MTV (Music Videos) scraper improvements and enhancements
• New freebase music scraper (with Artist FanArt support via htbackdrops.com)
• New Polish music scraper combining allmusic.com,merlin.pl, and lastfm.pl
• New mymovies.dk (Multilanguage) movie scraper (*commercial)
• New fdb.pl (Polish) movie scraper
• New cinefacts.de (German) movie scraper
• New filmdelta.se (Swedish) movie scraper
• New world-art.ru (Russian) movie scraper
• Updated imdb.cn (Chinese) movie scraper
• New cine-passion (French/English) movie scraper
• Fixes and additions for the mymovies.xml scraper

Skins:

• Confluence is the new default
• PM3.HD set to secondary
• Removed legacy PM III (farewell old friend)

Windows-Specific:

• Changed from Open GL to DirectX for GUI and video rendering.
• Added Crash Dump for Windows
• Support Milkdrop visualizations

Linux-Specific:

• Added support for Debian building and packaging to the XBMC SVN
• External libraries options when compiling XBMC for Linux making it more distro agnostic
• Support for PPC (PowerPC) processors in XBMC for Linux (OpenGL support required)
• Avahi Zeroconf (Zero Configuration Networking) for XBMC webserver
• Added DeviceKit.Disks integration
• Added DeviceKit.Power and ConsoleKit.Manager integration

OS X Specific:

• Logitech Harmony Universal Remote support
• Added support for CoreAudio API and removed the PortAudio API code
• AC3 and DTS digital audio pass-through to SP/DIF on Apple TV (thanks to CoreAudio)
• Support for running external Applescripts
• Support for command-tab application switching
• support for OS X Spaces (virtual desktops)

Live-Specific:

• New installer with disk partitioning support, network setup and language selection
• Uses Beatzeps08’s variation of duduke’s great “spinner black” usplash theme! Thanks Beatzeps08!!
• Based on Ubuntu Karmic
• NVIDIA drivers: 190.53 (VDPAU included on supported GPUs)
• ATI/AMD drivers: Catalyst 9.11
• Includes the magic tvheadend package, which brings live TV in XBMCLive
• The plugin “SVN Repo Installer” is also included, thus installing new scripts/plugins/skins will be easier

You can download XBMC 9.11 here (Linux, Mac OS X, Windows 7, Windows Vista, Windows XP)