It's always great to spend some time geeking out with Bart De Smet. As usual, he has a lot of technical details to share and only so much whiteboard real estate. Bart is still deeply engaged with Rx (evolving it, putting it to new uses, making it even more general and capable). How so, you ask?
Well, ask Cortana. She will tell you that, in fact, Rx is one those wonderful things that make her so asynchronously capable and reliable at managing your calendar and the growing list of other personal things that you have her do for you. (I haven't actually asked Cortana this, so this is an exercise for the reader...)
Bart, how exactly is Rx used in Cortana?
Remember our old friend IQbservable?
Look, a whiteboard! (But, of course, we have catching up to do beforehand. Be patient.)
Tune in. Enjoy.