It’s been a long time coming, but according to a message posted to the Google Voice Twitter account this morning, as well as a posting on the Google Blog, Google is getting ready to open up its free Google Voice service to more users. According to NBC’s Janet Shamlian, who did a piece about Google Voice for the Today Show this morning, the service might actually open up for all U.S. users today – though as much as we would like this to be true, we think the reporter got this part of the story wrong. If you haven’t done so already, however, now would be a good time to get your invite request in, as Google will first let in users who requested invites before opening up the service to everybody.

We have used Google Voice ever since it was still GrandCentral (Google acquired GrandCentral in July 2007) and couldn’t be happier with the service, so here is our rundown of what you can expect once you get your own Google Voice number.

Just a few days ago, we reported that Google had acquired about 1 million new phone numbers, so we aren’t too surprised that the company is getting ready to open up the service to more users now.

How Does it Work?

Just like GrandCentral did when it was still available, Google Voice (GV) will assign you a new number, and then you can set up GV to forward calls from this number to your cell phone, home phone, or office.

For calls within the US, GV also allows you to place free calls, though instead of running through a flash widget or a desktop app, GV will actually call your phone and then place the call, so you will still use your cell phone minutes. Google Voice also offers cheap international calls with prices that rival those of Skype and Vonage.

Nothing on your own phone changes, of course, so when you place a call, your home or cell phone number still appears on your friend’s caller ID, though you can always opt to call your own GV number first and then connect the call from there.

GV features a Gmail-like, stripped down interface that puts transcribed voicemails and recent calls at the center of the screen, with the ability to also see recently placed and received calls, your contacts, and other standard features you would expect from a telephony app.

Our Favorite Features

• transcribed voicemails: whenever somebody leaves a voicemail, GV will transcribe the message as best it can (this only works for English right now). These transcripts are then forwarded to your email account and you can also opt to receive an SMS notification.
• listening in to voicemails: whenever you receive a call and decide to let it go to voicemail, you can also choose to listen in and even pick up the call if it turns out to be an important message. This feels just like the old days when answering machines with tapes were still a novelty.
• call screening: one neat option in GV is the ability to screen calls. If you activate this feature, callers will be prompted to leave their name once they call, and once you pick up the phone, GV will play the name back and you can choose if you want the call to go to voicemail or if you want to actually speak to this person. You can opt to let all unknown callers who are not in your Google address book go through this procedure or just those calls from callers who have blocked their caller ID.
• recording calls: at any time during a call, you can press 4 and the call will be recorded. This only works for calls you receive on your phone for now, and doesn’t work for outgoing calls.
• conference calls: just ask participants to call your GV number and once more callers call in, you can just conference them in – this works for up to 4 callers.
• switching phones: if you want to switch phones during a call (say you took a call on your home phone and decide you want to take a walk and continue the call on your cell), just press * and all the other phones will ring.
• SMS: you can send and receive text messages from your GV account
• integration with Google Contacts
• it just works: the call quality is good, we didn’t experience any outages during the last few months, and calls aren’t dropped. GV does what it says it does, and it does it well.

But What About Making Calls from my Phone?

As we mentioned above, making calls from your own phone will still display your old caller ID, but at least if you have an iPhone, you do have the option to use GV Mobile, which provides a nice phone interface and comes in a free (iTunes link) and paid version (iTunes link).

A Few Things We Would Like to Change

• the ability to set your cell phone to display your GV number in the caller ID  – this is still a big barrier for users who might otherwise be willing to switch. As long as your old number still appears in the caller ID, others will continue to call you on that number and will continue to route around your fancy new GV account with all its bells and whistles.
• no call chains: you can’t set one phone to ring first and then, when nobody picks that up, transfer the call to the next number (GrandCentral offered this feature)

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