Netflix in it's attempt to move more to a hybrid social site introduced the concept of "faves" a little while back. This is essentially a watered down "friend". Where as a "friend" is probably someone you know in real life, and therefore netflix allows you to see basically all the information they can see about themselves, a "fave" is someone you probably don't know. Therefore you can only see limited information about them such as 5-star rated movies, and genres or actors they watch a lot of.
Each potential "fave" has a similarity percentage ("friends" have a percentage as well) based on some netflix algorithm which is a quick way to see (hey!) how similar your movie watching tastes are. So as I sometimes do I was on one of the netflix pages where you can see potential "faves" and saw a person with an 86% similarity percentage; which is very high. In fact this would be the highest of any "fave" similarity percentage I've seen yet. With all this "friends"and "faves" stuff netflix also introduced user names which if you don't choose one will be auto-generated for you from as far as I can tell your first and last initial, and then a string of digits. This specific "fave" (who by the way also had Kevin Spacey as the most watched actor...my favorite actor) had an auto-generated user name of "MZ 123456". (Yeah I changed the digits).