I thought that was curious, so I put one of their code samples to the test:

Swift WTF: http://swiftwtf.tumblr.com/image/88465530183)

But it looks fine on my machine (Xcode 6.2): http://imgur.com/rJU7lcx

This is a blog whose latest entries deal with Xcode 6.0 beta 3 (out of at least 7 eventual betas, many of which made substantial changes to the language). Right now, the 'standard' Swift version is Xcode 6.1's (Swift 1.1), and Swift 1.2 is in its third beta. So it's definitely not representative of the current state of the language (which was, admittedly, in pretty awful shape at that point in time).

Yeah, this is silly to talk about now. I'm sure you can dig up plenty of WTF things about the latest Swift, but few if any of these examples are still valid.