Above the show floor hubbub at last week's CTIA, I think I got a whiff of what the future holds for mobile voice services as we move towards fourth-generation networks in the U.S. – and it sounds like a big ball of static, hiss, and dropouts.

You see, even though AT&T Inc. (NYSE: T) and Verizon Wireless still seem somewhat leery of Skype Ltd. and other voice-over-IP clients, the move to Long-Term Evolution (LTE) and – to a lesser extent – WiMax makes the switch to cheap, or maybe even free, packetized voice services more likely. (See US Carriers Still Lukewarm on Skype and Skype Ist Verboten!)

LTE and WiMax are all-IP networks, so the carrier has to offer a voice client anyway. Even though AT&T and Verizon currently aren't willing to see voice as "just another packet" on their networks, you have to wonder if that could change as the carriers deploy LTE during the coming years.

Voice services are already getting cheaper, while carriers are bringing in more revenue from their data services. So, despite protestations, it's not hard to see "best-effort" voice services as a distinct possibility on proto-4G networks. After all, why spend valuable time and money on a service for which people will pay less and less?

Meanwhile, as data becomes the money-maker, carriers will move away from offering so-called "unlimited" data packages. Verizon has already said that it's less keen on all-you-can-eat data offerings.

This is how I see it going:

You buy a data package and get unlimited calling thrown in for a nominal fee, or even for free. The call quality isn't necessarily great, because the carriers aren't too worried about quality-of-service with this best-effort offering.

The data packages are segmented into standard user, family, and heavy user style packages. A heavy user gets, say, gigabytes of download capacity, while the standard and family packages offer less.

Enterprise users and others that want better voice services can still get them – but it'll cost more money to get any guaranteed service levels.

With the introduction of Skype on the iPhone, BlackBerry, and Android handsets, it seems to me that other VOIP services will inevitably move in the direction of cheap and cheerful calling plans. It might be different if carriers can find some way to make better revenues on voice, but otherwise I fail to see the motivation for better quality voice offerings in the years to come. (See Skype Lands on iPhone.)

— Dan Jones, Site Editor, Unstrung