The milestone that Kevin DuBois is cheering about is that Canonical's display server for the Ubuntu desktop and Ubuntu Touch is working with the big four Android GPU vendors. Mir-enabled Ubuntu images now work for the Nexus 10 with an ARM Mali T-604 GPU, the Nexus 4 with a Qualcomm Adreno 320, the Nexus 7 with a NVIDIA Tegra 3, and the Galaxy Nexus with PowerVR graphics.
Kevin added though, "The only disclaimer on the video is that some of the code hasn’t trickled to the images yet, and the tablet support is still a work in progress. Onwards and upwards!"
Additionally, having done most of this heavy lifting for Android GPU driver compatibility outside of Canonical/Mir is the libhybris open-source project that serves as a compatibility layer for Android libraries and drivers on GNU/Linux platforms.
Anyhow, Kevin DuBois wrote about the four major Android GPU drivers/vendors running with Mir in a blog post entitled Mir Device Showcase! He also shared the video embedded below.