NBC reports that the service will start to be publicly available today and Google confirms the news: "Invites to people on reservations list starting to go out today." In March, Google Voice was released as an upgrade to the existing GrandCentral users and you could request an invitation using a form from Google's site.
Network World found that Google reserved one million phone numbers from Level 3, preparing for the public launch of the service. A major hurdle slowing the adoption of Google Voice is getting a new phone number, but Google tests a feature that allows users to port their existing numbers to the service.
Update: Apparently, Google Voice won't be publicly available, but you'll get an invitation if you've previously requested one. "We are happy to share that Google Voice is beginning to open up beyond former GrandCentral users. If you requested an invitation on the Google Voice site or previously on GrandCentral, keep your eye out for an invite email," says Google's blog.
{ via Lifehacker }