But I still think people would rather start using something else. It would only give Google the opportunity to start advertising Google+ as the FREE social network on TV and elsewhere.
Meanwhile, CPC for Facebook ads is much higher than 2 cents - or I'd be spending a lot more money there. $.2 - $.4 is more common.
So assuming a FB user checks an average of 10 pages a day (which sounds about right, given, say, a few profile refreshes, a couple of message replies, a photo or two, maybe a game) that's 3000 page views approx over a year, which is 15000 ad views, giving us about 12 clicks at about $.3 each, for a customer value per year of closer to $4 or so.
Having said that, $5 per year still isn't very much to pay...