Google's decision to run different software on its Nest smart displays has led to a confusing jumble of features. Some displays have features the others don't, and Google is always testing something or another that further muddies the waters. Today, Google has started rolling out a change to the Now Playing interface on the Nest Hub. Instead of volume controls, you get "Move to" casting controls.
The Now Playing screen shows up on Assistant displays when you're casting to a speaker group. Currently, it allows you to change the speaker volume for each device (below). There's also an overall volume slider at the top. The new interface from our tipster instead has "Move to" under that main volume slider (above). With a tap, you can instantly move playback to a different group or individual speaker.
The old UI on a non-Nest display in the same network.
Changing the cast target looks like a useful feature, but maybe not more so than controlling individual speaker volumes. Non-Google Nest speakers appear to still have the old interface. I can also confirm my Nest Hub still has the old interface. If this is a full rollout, it's starting slow. However, it's just as likely Google is doing a test, and the UI could revert to volume control.