The language also had some false starts (in 1.0 / 2.0) and some interoperability baggage (with ObjC). But arguably, it is in a steady path now. If Apple continue the current path, in 3 or 4 years, it will be much more interesting.

Of course, in our industry, whether anything can continue the current path for another 3 or 4 years is a big unknown itself.