est's CEO, Tony Fadell, is known as being the second man behind Steve Jobs responsible for the iPod. Back when the first iPod was released nobody really thought it would turn into an incredibly profitable empire for Apple, but the vision partly on behalf of Tony Fadell helped shape the space. While Google might not acquire a company at such a high price tag merely for the talent, it certainly factors into the decision. When you have someone with a proven track record at one of Apple's biggest competitors, and he's put all his eggs in Nest, it starts to look like a little less crazy of a move. For all we know other competitors may have been eyeing Nest as well, and this move could have been preemptive to secure the company and the space early on.
Also, what many people may not be aware of, Google Ventures, Google's own venture capital investment arm, was an early investor in Nest. In fact, Bill Maris, one of Nest's four board members, was a partner at Google Ventures. Given that Google already had a pretty sizable stake in Nest, the real cost of the acquisition might not actually be as expensive as the advertised price tag. Since Google Ventures gets a share of the returns of the sale, the real price for Google is probably a lot cheaper than 3.2 Billion dollars.