The current Android-Mesa stack is capable of accelerating the Android window compositor and allows existing Android applications to utilize full 3D acceleration without any modifications. The work Chia-I has done includes improving the OpenGL ES support, adding in support for new OpenGL extensions, and writing a new EGL driver. This new EGL driver is called egl_android. He has also had to add support for non-X windows systems to Mesa's OpenGL ES/EGL stack, since Android does not use the common X.Org Server but its own system.
Chia-I Wu announced this Android-Mesa work in this mailing list. All of Wu's work currently is not found in the main Mesa repository but rather this Gitorious branch. Previously Chia-I has worked on FFmpeg support in Android and other projects for Google's mobile Linux platform.