A couple of months ago I gave a technical talk about blockchains at a local Ethereum meetup. The presentation is essentially a knowledge remix of all the publicly available Solidity reference material with some software engineering concepts, architectural suggestions, challenges and detailed breakdown of the DAO hack thrown in for good measure.
You can view slides from the talk here or over on github. If you've ever wanted to get started writing software for Ethereum - or blockchains in general - then I highly recommend you take a look and save yourself some research!
(Use the arrow keys to drive it & P to show slide notes; and apologies for hijacking your scrollwheel. It's the slideshow framework's doing, I swear!)
Play along on YouTube: