We use Solar City, and our system works out to 16.7 cents per KWH this year. As with Verango, it does go up about 3% per year. I live in the central valley of California so we use a lot of air conditioning and have a pool, and we are on an electric well, so this was a massive savings for us in the summer and break even in the winter even when we factor in the 'rental' payments.
They size the system so you still pay for tier 1 from PG&E (parent is right, no point buying solar energy that is more expensive than grid). If you do cut back and push electricity to the grid, PG&E will actually pay you for it.
Two caveats to that - when you go solar, PG&E moves to billing you only once a year, and that can be a significant shock when you get the bill. They also only pay you something like 6 cents a KWH, so its not worth over-sizing a system just to get a check.