I received my Google Voice number a few months back and dig it so much that I have told others to sign up to get their invite, but really who wants to talk face to face anymore. I mean hell, I have Google Voice so I dont have to talk. The beauty of it is, if i want a specific person or group of persons to hear specific voice mail, I can set it up so that I can answer the question in the voice mail that they hear.
Beginning today, Google Voice will have the option of inviting a friend. This is going to be a slow roll-out, so it may not display for a few weeks. Initially, you will only be able to invite up to three people, but as time goes on, Google is planning to allow unlimited invites.