Keith Whitwell of VMware (formerly Tungsten Graphics) has been hacking away at a new i955 driver for this extremely promising graphics driver architecture. While the open-source ATI/AMD developers have been hard at work on Gallium3D support and the Nouveau developers are solely focusing on Gallium3D for their OpenGL support, the official Intel developers haven't dabbled too much with Gallium3D. Keith Packard's crew isn't too sure yet whether or when they will invest all of the work in getting a Gallium3D driver up and running, considering all of the work they have been putting into their "classic" Mesa driver.
There has been a simple i915 Gallium3D driver created in the past by Tungsten Graphics / VMware, but now Keith Whitwell has restarted his efforts on the i965 driver, in the appropriately-named i965g-restart branch of Mesa. He restarted work from their DRI driver and copied the i915 winsys layer. Just five hours ago after working on thousands of lines of code this new driver and winsys are compiling. Albeit it's just compiling and is not a full-fledged working driver at this stage, nor will it likely be anytime soon. However, it's a start.