Do you have any evidence that Google Voice records phone calls without a user's explicit permission? I was never referring to voicemails (which are rarely used these days anyway).

I also don't see how you can make the argument that passive recording of everyone around you is the same as Facebook only receiving data that a user proactively sends it (ie. status updates, photo uploads, etc.).

Finally, even if we were to accept your slippery-slope arguments as true, why not go further down the slope and claim that the internet shouldn't exist either because massive data sets about your lives are already being mined and are at risk of nefarious use?