Quick comment: don't expect Daala to be a mature codec for a while yet. To quote Monty "Writing a complete new encoder from scratch is a small task compared to the time required to then tune that new encoder into efficient operation. Incremental changes allow demonstrable, steady progress."
The downside is that incremental changes leave you stuck in a sufficiently large local maximum, which is where Daala comes in.
I'm not, but I am expecting it to be 2x as efficient (with the same quality) as VP9 and HEVC, if it's going to arrive that late in the game. I don't think anything less than that will work for them (won't be adopted), because then the switch won't be considered worth the trouble. Hopefully they pull it off.
The next generation of video codecs won't be as expensive a switch as the mpeg2 or h264 era. If a codec shows enough space efficiency, you could just implement an opencl or compute shader variant of it to run GPU side, which will outperform cpu rendering in power efficiency and time by an order of magnitude, and properly tuned would be in the ballpark for dedicated hardware decode time.
In the same way dedicated audio decoding hardware went out the window when cpus got fast enough dedicating die area to it just because excessive even if it was more efficient and faster, I think the same thing will happen (soon) to video decoding, where the extra dedicated decode hardware just isn't worth the hassle when well optimized gl 4.3 compute shaders or opencl enable efficiency and performance if not close to the dedicated hardware, close enough to not justify having it.
It almost already wins the efficiency gain, because just by making dies larger to include that extra circuitry increases the power ceiling of the device. Being able to genericize die area doesn't give at-runtime power gains but overall you can save juice not wasting die (though power management has gotten so sophisticated it can outright shutoff parts of a chip, so it might be able to eliminate that downside).
But simultaneously the gpu hardware in phones (tegra 4 / snapdragon 600 era) is reaching the same threshold cpu audio decoding reached - it becomes silly to waste the die when the performance is close enough.
And even if this isn't the generation where dedicated hardware goes out the window, it will be the next one, and this one will be close enough it will be like the late 90s with audio where the experimentation begins.
Codecs aren't parallel enough to work well on GPUs; parallelism in general hampers compression efficiency.
Anyway, audio resolution hasn't increased anywhere near as much as video resolution. 48 kHz sample rate, 16 bit sample depth per channel is still the highest reasonable, and we've had basically that since CDs.
Whereas internet video has gone from CIF to 1080p, a resolution increase of over 20x. And 4k is being pushed now for another 4x increase.
The point is that audio resolution peaked, and additional returns were negligible at best. Video has the same effect occur somewhere around 300 PPI at 6" view distance, 200 PPI at 12", etc - and between 90 and 150hz refresh rate. Color fidelity is also near its limits on some high end IPS panels.
Past those points, most people don't notice the difference, just like how most people don't notice the difference between 16 and 24 bit audio at 44.1 or 48khz sample rate. Once the vast majority of people no longer see a difference, the technology peaks. I think video is (finally) approaching that territory in the next 5 years, at least in 2 dimensions. I feel holographic 3d video will see a boon after that, and not the eye trick 3d crap we have now.
The downside is that incremental changes leave you stuck in a sufficiently large local maximum, which is where Daala comes in.