Some two years after purchasing GrandCentral for a reported $50 million, Google has announced it is relaunching the uber-phone service as Google Voice. [via TechCrunch]

In a nutshell: It's gmail for your phone. And then some. You get a new number (that's the big downside, at least initially) from which you can get a ton of utility from the voice side of your phone. Frankly, it's almost too much to list here. But we'll give it a shot:

  • Call screening: Listen in before accepting a call.
  • Block calls.
  • SMS: Send, receive, store SMS messages. Read, search and forward them from the Web.
  • Place calls: Call any number in the U.S. for free.
  • Take calls: Your Google Voice number can ring a number of phones.
  • Call routing: Select which phones ring based on who is calling.
  • Voicemail transcription: Get a voicemail, and it's automatically transcribed and e-mailed.
  • Listen to voicemail online or on your phone.
  • Notifications: Get notification of voicemails via SMS or e-mail.
  • Personalized greetings: Have one for your friends. Another for co-workers. Another for your boss. Another for your spouse. You get the idea.
  • Conference calling.
  • Record calls. (legal issues there?)
  • Call switch: Pass the call off from one phone to another. (Just because you can!)

And many, many more! (OK, a few). There are videos to go with each of the above features, and a few more, over at the Google Voice page. For now, here's what you need to know: 

GrandCentral stopped taking new sign-ups a long while ago. But the lucky ones who got in in the beginning should have access to Google Voice in the next few days. Google will "be opening it up to others soon." Oh, and have we mentioned that all this is free?

OK, let's tie this in with Windows Mobile, shall we? We all know that a (current) WinMo phone basically is a mobile version of Windows (Windows CE) with a phone radio bootstrapped to it. This brings power to that end of things. Sure, there are third-party companies out there that will do some of what Google Voice promises (voicemail transcription, mainly). But now it's being brought under one roof. Seriously, go check out those videos.

All you have to do is give yourself up to The Google.