This is great! I have been wanting Netflix to do this for years.
It's perfect when you or your spouse are travelling on business and want to do something "together" in the evening. There are stories of Bill and Melinda Gates doing this back in the day with rentals and going "3-2-1-play" over the phone.
Seriously, why hasn't Netflix been doing this?
It was amazing when Netflix and Xbox 360 did this. They had it as a "Netflix" party and you and your Xbox friends can watch a movie same time and talk on headset or using empties