As an experiment to see how well Google Voice works, I decided to do a couple of things since I already have a Google Voice account (for about a year and never really used it). We use a sipfoundry based voip pbx at my office, I have a cellphone (a blackberry for now) and so I did the following.
1. Accessed GV and set it to DND (Do Not Distrub). This means any calls to the GV number go straight to Voice Mail (VM).
2. Set my cellphone (Verizon Wireless) via feature code to send my calls to GV that are not answered. With Verizon its *71(+GV number).
3. Forwarded my deskphone to send my calls to GV if there is no answer (instead of using the voicemail I have already on the sipXecs system).
I also had to set some options in GV to not send me TEXT messages (just email me) for missed calls and voicemails, and to also transcribe the VM.
Since I have a GV app for the Blackberry, and a BlackBerry Server integrated, I was all set to use my Google Apps account. Its a universal inbox of sorts, sends the VM as an email with MP3 attachment, and is TINY to download compared to some other methods. While the voice to text transcription is not perfect, it works, and its all FREE!
My only real gripes...
1. No sip URI for GV VM or GV account from the folks at Google.
2. Sometimes it transcribes my last name as "Crazy I Know". In that respect, maybe it knows more than I care to admit...
We'll be doing more with it later the in quarter, and will post back some findings.