After a year of effort the Raspbmc team announced it has reached the 1.0 milestone. This means the team is confident they've achieved a stable port of XBMC specifically designed to run on the Raspberry Pi and the image is ready to downloaded for free and copied to your ready and able SD card. If you were already enjoying the fruits of the early builds of Raspbmc, you'll need to do a complete re-install but that shouldn't be too much trouble since you probably store your content on a network drive or external USB.
Raspbmc 1.0 is based on the recently finished XMBC 12 Final and supports DTS decoding in software. This is in addition to many other codecs supported in software and you can purchase licenses from the Raspberry Pi Store for MPEG-2 and VC-1 hardware decoding for just a few bucks. A good move, since hardware decoding of today's most popular video codecs is almost certainly a requirement for any proper XBMC setup. Now, if the Raspbmc team would release their own custom case for the RPi then everyone would know what's going on just by looking under your TV.