Even if they did start the driver a while ago
Mesa itself is years behind.
I don't see AMD pushing a driver that doesn't even support OpenGL 4 for their brand new cards.
Now, there may be something where they announce more support. Maybe in particular for Android - I could see how Mesa might be far enough along for that, and it would probably be a nightmare to try and port fglrx to it and slim it down enough to fit on a phone.
Let's hope they announce they are opening up UVD, open sourcing their OpenCL work, adding a bunch of OSS developers, and committing to having the OSS drivers available at hardware launch time. All 4 of those would be pretty major announcements. I'd be very happy if any single one of those was the big announcement coming up.