Beignet managed its first open-source Intel OpenCL release earlier in the year but it's taken some heat for not being Mesa/Gallium3D-based but rather its own code-base. Intel still is using a classic Mesa DRI driver and they didn't want to write a GPGPU-only Gallium3D driver where they could then leverage the "Clover" OpenCL state tracker.
While Intel has taken a different approach, Beignet has been making a lot of progress since Intel has several full-time employees working on the open-source code.
As you can see from Beignet on Anzwix, our latest Linux news source, there have been a fair number of interesting commits going into the project recently -- including a number of worthwhile commits this week.
A commit that happened worth pointing out today is enabling GL sharing with a new EGL extension. The work is about having an EGL extension in both Beignet and Mesa so that buffer objects / textures / render-buffers from the Mesa driver can be shared with the OpenCL driver layer from Beignet. While the code is now in Mesa, the new EGL extension isn't yet found in Mesa.
This OpenGL buffer sharing support is being implemented via the cl_khr_gl_sharing extension on the OpenCL side. This new Beignet code is replacing an old "hacky" implementation they had for sharing 2D/3D textures.