User blog comment:ThePK/User Cards/@comment-3181121-20120116182147/@comment-3986064-20120116184138

The point is to:


 * 1) Becoming someone's (at least temporary) profile, if it lacks any content
 * 2) Becoming the part of someone's profile
 * 3) A simple card where some fast info on the user can be found out, if we contribute to such a project, new users might learn who does that and who does that

If it's not contributed to, it will be an ineffective way to inform users on certain things about other users, but not useless