[... without nowhere in its slide a mention indicating where Clang comes from or even a link to Clang/LLVM project web site]
They didn't because everyone in that room are professional developers who don't need (or want) LLVM to be defined to them. Just as they don't want or have the remotest need for them to post a link to the LLVM site (?!). Nobody there would need this, this is silly, and besides, it's a google search away. Anyways, the main thing is your mistaken judgements in the first place, see Bright's response.
To the question: "Well, where is the C++ Content?" - see 1:30:
"And the topic is: Compiling Objective C on Windows using Visual Studio ..."
If you saw the other talk (which was excellent: https://channel9.msdn.com/Events/Build/2015/3-610), clearly there is much guardedness up with regard to this whole issue as of yet, with a tentativeness to reveal all the details. Even in that other talk (at the very opening) they mentioned that the talk got renamed over and over.