With one glitch (the update doesn't work under Lumia Denim - you have to remove the application and reinstall, and even then content crashes!), I have to rejoice with thousands of other Windows Phone users around the world in a complete re-write of the Netflix client, this time bringing the much awaited user profiles (so your choices and your kids' don't have to be mixed!), plus automatic post-play, a redesigned UI, Cortana integration, and much more....
Here's the quoted (somewhat terse) changelog for the new v4.0.0.13:
New User experience
Profile selection
Post-play
Better video quality
Application tile
Content pinning
Cortana search
And here's the new version in action under Windows Phone 8.1 Update 1 Developer Preview on my Lumia 1020 (no doubt the Lumia Denim issues will be fixed in short order):
Profile selection, just as on iOS and Android - phew! The carousel layout is new too, and much closer to the interface on other mobile platforms.
Browsing video genres and the graphical title browser in action...
The post-play feature lets you move seamlessly from one episode of a TV show to the next...
Disaster under Lumia Denim on the 830.... no doubt Netflix's engineeers are coding up a DRM fix even as I write this!