Olivier Halligon with a great four part series (1, 2, 3, 4) on pattern matching in Swift. This has been in my list of pending links for weeks now, but I wanted to wait until the series was finished before posting it. You should read all four parts.
I liked this illustrated summary of the major Swift 3.0 changes by Paul Hudson. It's all very well seeing the proposals fly by, but code examples really help to show the impact of the changes and that's what you'll get here.
New networking library from Elvis Nuñez which shipped a 1.0 this week. It's designed to be a lightweight wrapper around NSURLSession and friends, with good support for testing and simplicity at its core. Worth taking a look at.
I really liked this article by Natasha on adding an animation to a view using Swift protocols. It takes a simple, common problem and shows a clear benefit to the protocol oriented approach.