You need to call Swift's bluff with AnyObject. That's unsafe and was only necessary to bridge to Objective-C where you can call any method on any object.
When you write an iOS app you're constantly interacting with Objective-C. The moment you're using JSONSerialization–and unless you're shipping your own JSON parser, you're not avoiding it–you're getting back a nice Any that you are almost certainly going to work with, possibly implicitly, using AnyObject. My point was that switching the SDK to use Swift would not help fix this issue, and I think I've shown that you'd run into similar issues even without the use of the force unwrap operator as you implied previously.
I think we are in general agreement?