We ran our Salesforce1 Lightning series of challenges at topcoder last fall after the announcement at Dreamforce with much success! Since the framework was beta we knew that we were writing code on the bleeding edge. There was a lot of trial and error involved but you came through in the end by building a large number of awesome components.
Its been roughly six months since the release so we are starting to see more and more Lightning resources for developers. Features and functionality are coming fast and furious but if youd like to keep up with development or get started building Lighting components, here are some new resources for you!
Trailhead teaches you how to build cloud apps for free with fun, interactive tutorials. Stand out by learning in-demand Salesforce development skills. There is a Lightning Components module that consists of 10 or so videos with associated learning challenges. Definitely start here.
My buddy Paul is doing some great videos, tutorials and blog posts on his site for Lightning components. They are definitely worth checking out.