THIS TALK SLIDES - https://speakerdeck.com/pablomouzo/speed-is-a-feature
Performance is a feature - http://blog.codinghorror.com/performance-is-a-feature/
Marissa Mayer at Web 2.0 - http://glinden.blogspot.com.ar/2006/11/marissa-mayer-at-web-20.html
Psychology of Web Performance - http://www.websiteoptimization.com/speed/tweak/psychology-web-performance/
New Relic - http://newrelic.com