That said I'm a developer with around 20 years experience under my belt so the ability to learn new stuff quickly is in the blood, and I've got the advantage of working for many years with different development paradigms.
And in principle it can revolutionise the way scripting works in OSX. From the few test I've done, when it will be stable it will be a fast nice replacement for many of my python, sh and ruby scripts.
Moreover, I think that this can set the basis for a better and simpler concurrency model in iOS too. But we will see.
The only thing I find disappointing and error prone is the different passing behavior between structs and classes, but I assume that we will get used to it.
Swift is great! Even with my exposure to various C+Objects syntaxes over the years, Objective C just makes my eyes hurt. I wrote a couple of iOS apps and I never got used to it. I just don’t care for it. It’s really just a matter of personal prefs, I think, because others really like Obj-C and I grant that it must be possible! ;)
The Swift syntax is airy and easy to read. I felt like I was breathing fresh air, if that makes any sense. I converted the SpriteKit walkthrough PDF examples to Swift from Obj-C as I went along. Very straightforward. There were a couple of things that took a few minutes to figure out, but it was all very logical. The Cocoa APIs seem to fit Swift nicely.
I am very happy about this new language. As someone else said above, its like a heavy weight has been lifted. It really is that affecting.
Having said that, Swift is not nearly as intimidating as Scala.
You're presenting mainly the language, which makes senses but might be already ticking boxes with at least part of the audience here which is already familiar with Haskell, or Rust, or OCaml, etc.
So, it's great to see the features and syntax, but what would be great is use Swift to make a tour of the API for iOS newcomers :)