MatchKey is a service to make personal preferences and behavioral data secure and transportable using a desktop application. Your interactions with movies, music and blogs on member sites builds a profile that exposes tastes and preferences without disclosing personal information.
The MatchKey system is attribute based, focusing on blog postings, video, movies, and music CDs. There are 72 attributes. Your interactions will personalize your web-based experience on member sites.
In the beginning, this will probably appear as a discovery or recommendation widget on a website or blog. If you interact with the content of that widget you acquire recommendations.
MediaPost Publications - I'll Take My Profile To Go - 10/26/2007-click to read complete article
From the article:
. . . visual representation of your personal preferences. . . It knows a lot about what you like but nothing about who you are; we exclude all personally identifiable information for the key, so what it gives you as a user is something you can take around and share. . . it asks if you want to share your profile.