The big feature that GTalk claims is its voice feature. Given that you have a microphone and speakers, it’s actually rather nice. Users can only chat if both are using Google’s Talk client (available for only Windows XP at the moment). Once a user initiates a voice chat, the program makes a telephone ringing noise and will look something like this.
Placing a call to another user.
You’ll notice that Google tried to make the buttons look like a VOIP service (like Skype) that can call people on home phones from the internet. The buttons refer to using the voice features as a “call.” However, this is not VOIP and can only chat with other Google Talk users. Google wants it to be clear they are not providing VOIP in their license agreement:
3. Not a Telephony Service; Emergency Calls Not Available. You understand and agree that Google Talk is not a telephony service and that neither the Service nor the Client is capable of placing or receiving any calls (including emergency services calls) over publicly switched telephone networks.
This doesn’t mean that integrating VOIP later is out of the question. After Yahoo! recently bought a VOIP provider, adding this functionality to Google Talk seems like the direction technology is inevitably going.
When somebody calls you, Google Talk makes a different ringing noise and displays this:
Accepting a call.
That image speaks for itself, but you still haven’t seen the program on a call.
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