Mikey Campbell, writing for AppleInsider:

Introduced as part of iTunes 12.6, which is rolling out to users as of this writing, the “rent once, watch anywhere” feature lets customers watch content rentals on any iPhone or iPad running iOS 10.3 or Apple TVs running tvOS 10.2. Those operating system versions have yet to move out of beta, suggesting a launch in the next few days.

Prior to the change, rented movies were largely relegated to the device on which they were purchased. For example, a film rented on an iPad or Apple TV could not be transported to iPhone, or vice versa.

Huzzah. The one rental, one device model was painfully archaic. Long overdue.

Kirk McElhearn, in a Kirkville post:

Remember how you liked having playlists in their own windows? Well, it’s back in the latest iTunes update. Right-click on a playlist and choose Open Playlist in New Window.

Two good things in a single update. Nice.