The service allows subscribes to create personal accounts that track individual ratings and viewed shows to better tailor recommendations. Each account has the option to offer different parental controls as well.
While this feature is not available to all yet, the basic infrastructure is already launched on the Apple TV. According to a Netflix rep, those who previously set up profiles when using the DVD service will now see those profiles show up on the Apple TV.
Profiles cannot be changed at this time and additional users cannot be added until later this summer when profiles can be set up on the web and accessed from the Apple TV and other devices.