The discovery of the live audio pins immediately led to lots of speculation about using the device for VoIP. Although to be honest, having used many large screen "smart phones" over the years, the ergonomics are wrong. Without Bluetooth using the iPod touch as a phone will be pretty tiresome. But the general consensus seems to be, it looks like an iPhone, why shouldn't it be able to make calls?
Shortly after the discovery of the live audio input pins, the same people hacked a mic in a dock connector (via Engadget). Now all that was lacking was some VoIP software...
A couple of days ago reports surfaced that the SvSIP stack has now been ported (via TUAW) and is being tested and that it's been confirmed that registration and signalization is working.
The translation is that "it all just works". As far as I know nobody has made an actual voice call yet, but all the right bits of software have already been written, and just need to be connected together. It's just a matter of time before that happens, and the fact that people are willing to go to this length to hack VoIP onto a device which out of the box fundamentally lacks even hardware support is telling.
Mobile phones have been commodity items, at least in the UK and Europe, for several years. What the drive for VoIP on the iPod touch is telling me is that the network providers, and the infrastructure they provide that sit behind the telephone calls you make, are starting to become exactly that. Infrastructure. The network of cell towers are just another commodity, and can be swapped out and replaced by a different infrastructure, in this case WiFi, without the user noticing much of a difference. The interesting stuff, the packet data level, sits on top, transparently.
This has been rubbed home to me by two things, the Skypephone which I've got on loan from Three, and the realisation that I haven't actually used my fixed line at home for several months now. It sits there, carries my ADSL connection, and as a consequence my phone calls which are now almost exclusively done over VoIP. But actual POTS calls? Not for a while...
The mobile network providers are dinosaurs, as are the fixed line telephone companies. It's going to be interesting to see it they can reinvent themselves, as Three are trying to do with the Skypephone, and provide what people actually seem to want. Commodity bandwidth.