In a recent post by Rich Tehrani from TMC, he quote a response from SpinVox about Google voice:
Google is entering a marketplace that continues to be led by SpinVox, the world's largest privately-held speech technology company. We're excited by the launch of Google Voice because it will demonstrate the benefits of speech-to-text conversion and validate its deployment as a network service to an increased audience. We have already launched carrier-grade services with 13 operators - including recently with Skype - on five continents and SpinVox is in use by in excess of 30 million users. SpinVox's 97 percent accuracy in conversion is now the benchmark around the world. - Christina Domecq, co-founder and CEO of SpinVox
And this 97% are human results. I am not sure that Google will post any response but we need to wait for usability feedbacks from users.
I further wonder about Nuance's response to Google Voice..?