Hello:
I have created a Windows program to total your Google Voice minute usage - it may help you decide which VoIP plan to select, if you are porting out of GV.
You can find it here:
http://www.googlevoiceforcanadians.com/program-total-google-voice-minutes/I thought that I had posted this info before but I could not find it here. I know that I posted it at DSLReports.
So, if this is a duplicate post, I apologize.