I have...
27 invites accepted from my friends
15 invites accepted from one person away
6 invites accepted from 2 people away
1 invites accepted from 3 people away
1 invites accepted from 4 people away

Of these, 4 are my personal friends, the rest found my link online.

I have created a squidoo page which explains the basic Zenofon features. Check it out here:

http://www.squidoo.com/zenofon

Many of the signups under me originated from this page. Write your own Zenofon page, host it on wordpress, squidoo or a hubpage, and watch traffic pour in. Use your own angle. It can be a review, a comparison among voip services or just a list of features.