I'm watching the livestream and will yack about it here.

The big thing so far is the new "Google Home" gadget. The hardware is analogous to an Amazon Echo, but it's got built-in support for Chromecast and they're trying to be very clever about the sorts of instructions you can give it. One example command was "play Coldplay in the living room". So think of this as Chromecast + Sonos + Echo. Oh and they want to kill your alarm clock while they're at it, so you can probably instruct it to play some playlist at a given time in the morning.