I hate you google.
There I was, checking out the Nexus 4, thinking it was a very nice device but was too similar to my GNex to worry about upgrading, then bam, they come out with the price. If I trade in my GNex this thing is going to hardly cost anything. I hope I can resist.
With regard to the operators, this is really going to piss them off (well in the UK anyway, can't speak for the US and their disgusting oligopoly). The profit is tying new customers into a new contract for 18 - 24 months, now what incentive is there. As stated above, I see it's being offered for free from CPW on a £31 month tariff for 24 months.
That's £744, 600 minutes, data not specified, but I suspect would be 500MB. My £10 a month tariff gives me comparable usage and I can buy the phone for £280. Total cost over 24 months - £520. You'd have to be stupid to sign up to that.