Today, on the fifth birthday of TEDTalks video, we’re releasing a new list of the 20 most-watched TEDTalks over the past five years — as watched on all the platforms we track: TED.com, YouTube, iTunes, embed and download, Hulu and more … What a great, mixed-up group this is! Talks about education and creativity, sex and fish, whizzy tech demos and big questions about the universe … it’s a cool sna