Broadcom's Crystal HD video decoder is no longer as interesting as it once was since Intel, AMD, and NVIDIA GPUs are all doing a great job at hardware-based video decode (and in some cases, encode) on modern GPUs. Intel's open-source Linux driver has full support for hardware video encode/decode on recent generations via VA-API.
NVIDIA's binary driver continues to deliver a first-rate video experience with PureVideo HD hardware through VDPAU. The other recent change in the Linux video landscape has been open-source support that emerged earlier this year for AMD's Radeon "Unified Video Decoder" (UVD) in their Linux driver and exposed via VDPAU in Gallium3D. Simply put, for most systems there isn't any need now for a Broadcom Crystal HD video decoder.
While I've written several times about Crystal HD on Linux since there's an open-source driver found in the mainline Linux kernel's staging area, it's been about one year since I last heard of the Broadcom decoder.
Support for the Broadcom Crystal HD has been found in XBMC and MPlayer and FFmpeg, among other open-source video applications and even Adobe's Flash Player.
The news today on Broadcom Crystal HD under Linux is that a new open-source developer has taken up work on the code and is working on having GStreamer Crystal HD support as a plug-in. Guido Günther had ported the Crystal HD plug-in to GStreamer 1.0 and then most recently has been working on getting the plug-in merged for the gst-plugins-bad. As part of this engagement Guido's been splitting up the user-space Crystal HD library (libcrystalhd) and the firmware blobs and making other improvements.
Guido Günther says if the Crystal HD plug-in ends up being merged into GStreamer the next "great" step would be getting the Broadcom Crystal HD driver promoted to the mainline area of the Linux kernel outside of staging.
More details on this work can be found via Guido's blog. The code repositories for his work can be found on GitHub via libcrystalhd, etc.