VoIP peering has been gaining popularity over the past couple of years. Mainly because of the shift of technology and how end users demand new services from voice technology. When several voice providers peer over such a fabric as The VPF its also is the way of selling minutes to other providers and bypassing the legacy telcos just as BGP peering accomplishes on the backbone of Internet routing.
I hope everyone checks out the peering fabric and gets involved on what they accomplish by using such a service.