Am I missing something here? I'm genuinely curious why anyone would think it's a good idea to surrender control over something that directly affects their everyday comfort, especially if it's air conditioning in Texas.
This is an attempt to find a consensual market solution to the problem of building expensive peaker plants that operate perhaps a day a year. The marginal cost of electricity generation capacity is astoundingly high.
Part of Nest's angle is that Nest can learn and detect whether you are home. This lets the thermostat save you money when you're not home - and this is the key - it does so without any thought or input or effort by the customer.