Pros
For me, the best thing about working at Nest is the people. Super smart, motivated, and down to earth people (for the most part). We're also pretty lucky to be working at a company that operates like a start-up but has the resources/benefits of Google. It really is the best of both worlds. If you are someone who likes a fast-paced, demanding environment where you will have the opportunity to have true ownership at almost any level, then you will enjoy this environment. If you are looking for a slow-paced environment with no pressure and just want to play around all day, then Nest is probably not for you. We have incredibly talented people who are motivated by challenging problems and work extremely hard to ship great products. Don't get me wrong, we play hard too. Weekly BBQs and almost monthly beer bashes are great to socialize with colleagues outside of the office. There are also employee groups where people get together to go on bike rides, do bootcamp, kickboxing, play basketball, ultimate frisbee, and even beer drinking.
Cons
Nest had a huge year with the acquisition by Google, acquisition of Dropcam, international expansion, and incredible growth of the workforce. I think the company is feeling some growing pains at this time; however, it is understandable when a company more than doubles in less than a year. Also, perhaps some teams are too demanding. Hopefully we see this level out as more people join teams and off load some of the work, but at times people on certain teams might not have the work-life balance they'd prefer.