Google acquired Grand Central in 2007 for more than $50 million in just over a year after the company launched. Grand Central essentially centralizes all of your phone numbers into one prime number; therefore even as you change numbers work or mobile numbers, everyone will still have your primary number.

Google has now finally re-launched the service as Google Voice. New user registrations are still closed but will be opened in the coming weeks. Google says existing Grand Central users will be getting an email with instructions on how to take advantage of the new features that will soon be opened to everyone.

Google is set to add many new useful features, including voicemail, SMS, email transcription, text messaging, and a simpler user interface to let you easily manage your SMS, recorded calls, voicemail and other features. You will still be able to purchase credits towards making conference and international calls via VoIP. Screen shots can be found here.