IoT: programming language?

With focus on efficient sensors for IoT, C++ may become a language of choice for small "things".
Apparently both Intel and Microsoft think so.
In particular with new C++11 and C++14 features, the language may be usable (enough).

Getting Started for C/C++ (Eclipse) - Galileo & Edison @Intel

NuGet Gallery | Microsoft IoT C++ SDK 1.0.0
NuGet Gallery | Galileo C++ SDK 1.0.6

Another portable alternative,  likely to be more popular is node.js (or its new "fork" io.js).
Javascript and the Internet of Things- Postscapes
Building an IoT Project with Intel Galileo and Node.js | Dr Dobb's
Intel(R) XDK IoT Edition node.js Templates | Intel® Developer Zone

Apple Swift could be very interesting, since it is both efficient and high-level modern language,
is supported by Apple, with smart people and virtually unlimited resources...
When Apple starts making IoT gadgets, that may be a good choice.
HomeKit - Apple Developer
HealthKit - Apple Developer

Google's Go is less efficient for small devices, and is optimized for parallel programming.

Finally, obvious candidates are Java and C#,
since they could reasonably run on many platforms,
but GC (memory management) makes them less usable for "real time"...

Great diversity...