Here is the talk:

Another prominent pledger is Chris Anderson, the head of TED, who took the pledge this year and wrote about it in his new book Infectious Generosity.

https://www.givingwhatwecan.org/blog/press-release-head-of-ted-chris-anderson-signs-new-wealth-pledge-to-give-at-least-2-5-of-wealth-to-high-impact-charities-each-year