urlSpinVox, the service that translates voice into text messages, demonstrated its technology to journalists today, emphasizing that its dependence on transcription by human operators will in no way hold the product back. That said, presenters stopped short of saying exactly how often these call centers are used versus automatic transcription.

At one point, the company’s chief information officer, Rob Wheatley, said that SpinVox has at times needed to route all of its calls through humans, but that this reliance is expected to taper off as it collects more data relevant to voice recognition from carriers. As it stands, the company is touting an application it calls Tenzing, which speeds the transcription process. As automation picks up, calls could be transcribed and turned around in as little as four seconds. Still, SpinVox wouldn’t tip its hand as far as how close it is to full or even close to full automation of calls.

The journalists who attended the demo were reportedly impressed by the automated technology involved in transcribing the calls, but were left cold when the company declined to reveal more about the role of call centers in its current business model and how fast that might change.

Limiting the amount of human intervention in its call flow is imperative for the company to grow its revenue five-fold — the goal it initially set for itself in order to hit profitability by the end of 2009. In order to give it a boost in this direction, existing investors provided an emergency round of $25 million.

So far, the road has been rocky. Not only is SpinVox embroiled in a legal dispute with former vendors (payment hasn’t been remitted for what the company says were subpar services). On top of that, reports surfaced earlier this month that the company was having to pay employees with shares instead of salaries — a rumored gripe that hasn’t been resolved. Regardless, it seems to be forging ahead at full steam, with its chief executive, Christina Domecq, telling Moconews that SpinVox will grow from 30 million to 100 million users in the next three months. Whether or not the service will continue to scale up after hitting this milestone rests largely on weaning itself off of human call centers.

SpinVox has raised about $200 million since its founding in 2003. Its past investors have included GLG Partners, Goldman Sachs, BlueMountain and Toscafund Asset Management, Martin Hughes, Carphone Warehouse, ABN Amro, Gartmore and Allen, and several private backers. It’s unclear which of these existing investors ponied up the recent $25 million.

The company made news earlier this year when it landed a lucrative deal with Telefonica to cover its Latin American mobile operators — potentially bumping its userbase to150 million in the not too distant future.

SpinVox might also be helped by developers building applications on top of its now public APIs. Mobile apps have already appeared to integrate the service with social networking services like Twitter — an opportunity that Doulton says could be worth some $80 billion.