Here is what I have learned thus far, comments, corrections welcome. The Principle Behind GV There is an excellent YouTube Video that explains the principles of GV: YouTube - GoogleVoice's Channel So assuming you want to use the GV number as the only number you give everyone, here are some possible advantages and shortcomings: ADVANTAGE: between the market app for your phone and the web interface, you can shut off any "Visual Voice Mail" (Verizon) service you might have, save a few dollars a month and some phone memory. SHORTCOMING: The voice quality from GV is not as good as Verizon's but is acceptable especially given the transcription feature. ADVANTAGE: Voicemail transcription. Very cool. SHORTCOMING: Possible increase in Texting Costs. Assuming you do not have an unlimited texting plan, you need to shut off SMS text notification of new voicemail (defaults on I believe). You can receive email alerts for free, and if you use the Android GV app (and you should) you won't need either as the ap does the notification. You can outbound text for free thru the web interface, inbound texts to your GV number that are passed through do count as out of plan text messages so you'll need to get around that using email notification. If you are a big texter and don't have an unlimited plan, this is going to be an issue if you want to maintain the illusion of having a single number. SHORTCOMING: Possible increase in airtime costs. There are several caveats here. I will explain for a Verizon Wireless Plan with unlimited "In" minutes and the capability to assign 10 friends and family numbers as "In". "In" means unlimited airtime. Using GV for inbound and outbound calls, you will see two new numbers on your cell bill: for incoming calls including calls you initiate through the browser interface, you will see the GV number you chose. For outgoing calls made from the handset using the GV app, you will see some number in your area code or a nearby area code that your cell dials to make the connection to the person you are calling. The person sees the GV number on their callerID but your phone actually dials another number to connect. The way to get around these airtime costs given the Verizon plan scheme above is to add these two numbers to your Family and Friends list. Note that the phone does seem to dial the same number to make outgoing connections. You (and I) will need to keep tabs on that to make sure it doesn't change. I have heard about reliability issues but have none yet to report. I haven't noticed any impact to in call voice quality that you might expect given what I assume is routing through GV infrastructure.