Google is testing the option for Google Voice users to port their existing phone numbers to the company's Web-based telephony service.

Although Google Voice has become a popular VOIP service for some users, particularly with its ability to transcribe messages, it has always seemed like a supplement rather than a replacement for a "real" phone number. That's because, in no small part, you couldn't ever port your phone number over to the Google account. Instead you had to set up a new Google Voice number and then construct a system of forwarding calls to it.

But a keen eye at Engadget noticed last night that a new option was available - the ability to port your phone number to Google Voice for a $20 fee.

"Huge," was the initial reaction from lots of folks. And on the surface, indeed, this is a big deal, something that Google Voice users have long desired, and arguably the purpose behind the service - the ability to have one number that can "ring" and record all your phone calls. But after the news broke, Google contacted Engadget and others saying that this was only a test and only an option for some users, although it does "plan to offer this feature to all users in the near future."

For those who had their hearts lifted by the promise of moving a well-loved phone number to Google Voice, it looks like you'll have to wait a bit longer. And arguably, you should use some caution before shelling out the $20.

After all, Google is not a mobile phone service provider. Porting your number effectively ends your current service, and there may be some early termination fees for doing so. Furthermore, without a phone service provider, those ten digits won't work - ported or not.

Of course, Google could pursue that option, but that seems to be significantly further down the road than just the option to port your number. And if Google can do that - lets us cancel our old phone line, move our number, and have cheap calls, free text messaging, and decent transcription - then yes, that would indeed be huge.