The point that really drove home with this presentation was the malleability of Ruby. Rails really has made a web dev DSL out of Ruby. Rake has done the same for automation, and I think you'll soon see MacRuby become an exceptional DSL for making OS X apps.<p>This, I think, is the what makes Ruby such a bag of awesome. It has familiar syntax, and has borrowed a ton of great ideas from a variety of different languages to make it powerful. I've learned more from fooling around with Ruby (and the concepts it incorporates) than any CS class I've taken so far, props to Matz for making a fun language.