My wife and I have separate accounts because we don't want our profiles for recommending new movies to influence each other. We try to find a common movie, and if nothing jumps out as being a good match for both of us, we simply sit next to each other with our laptops and use noise canceling headphones. We have been married for almost 30 years, so this is not as isolating as you might think.
Personalisation is weird when they're not even dealing with people but households.
Householdalisation?