I have three questions about Google Voice that nobody’s asked yet.

Sure, there’s lots of fawning over the concept and twittering about “hurry up and convert my GrandCentral account to Google Voice”. Has anyone stopped to consider what they’re about to enter into by using Google Voice as their primary phone number?

Granted using Google Voice as your primary phone number isn’t a huge risk because Google Voice is acting more like a traffic copy than a phone company. Their voice service routes your calls and takes your messages. You still provide the actual phone service for making and receiving calls. However once you distribute your Google Voice number – it can be a royal pain to switch numbers.

The old GrandCentral billed itself as “one number for life” – and that’s a great goal. One that I’m very interested in testing now that you can receive SMS messages through the service. Let me ask you the three questions that nobody has thought to ask.

What happens if (1) Google starts charging, (2) has a prolonged outage or (3) I want to leave — and take my Google Voice phone number with me?

For the low low monthly price of — FREE — do you think you’re getting any SLA (service level agreement – basically a guarantee against extended outages)?

Nope

Should the economy slip farther into recession and ultimately depression, is Google barred from starting to charge for those phone calls?

Nope

What happens should you decide to leave — with your “one number for life”? Can you port your number out to another carrier?

Nope

See what I’m getting at here? Free is a great price. But nobody gives you anything for free.

Google wants to make money off advertising. If the advertising model doesn’t work will they move to a more traditional billing arrangement where subscribers pay by the minute? Will we all be stuck with yet another phone bill with more hidden monthly “cost recovery” fees?

Before you use Google Voice for your primary phone number – give some thought to the risks involved – even when everyone is so excited that nobody has though to start talking about them.