Anyone care to post a summary of the OP (a 15-minute video)?
Anyway...
He starts by talking about how he joined Google because he believed they really wanted to change the world. They are basically the only ones fighting for Net Neutrality, etc. He said Amazon had a similar culture when he was there. He goes on to talk about scaling and how it might be the biggest problem for a lot of companies. Basically, everyone is working on some kind of scaling problem and it's usually for a stupid "cat picture project" (social networking). Later in life, you realize there are more important things (specifically, health related in the video), but it's too late because these tasks require math, stats and domain-specific knowledge. We are mostly lacking the domain-specific knowledge. He talks about how you may wish you could go back in time to tell your younger self to do something more meaningful. He challenges everyone to learn something new and make a difference. With about a minute to go he's puts his money where his mouth is and quits his job.