I am mostly excited about the HTML5 video codec that will reduce bandwidth, that will help a ton.
Too bad they're using VP9 which is barely better than a good aggressive H.264 encode. H.265 (HEVC) meanwhile blows VP9 out of the water, too, no matter what Google claims. Not to mention VP9 only seems to support 8-bit color depth - No Hi10p or similar. H.264 and H.264 support at least up to 12 bit color depth.
The only real advantage of VP9 is no licensing issues. But if they're really concerned about quality and bandwidth they need to allow those with legit licenses to be able to use H.265 as well. It can be resource intensive but the same couple be said for high-end 1080p AVC encodes when they were introduced nearly a decade ago. More and more devices are going to support HEVC in hardware, the newer graphics cards do. Heck even the Snapdragon 810 has support.