@wkempf: I agree with you on your opinion of IObservable vs Task. Tasks are great in their place but if IObservable is the right decision because of a reoccurring event then you loose a lot of composition options if you return a Task instead. Too bad I can't give you a plus one
@ljw1004: I also think these async tips have been very informative and would love to see more on the subject in a more in depth fashion.
@luzi:I admit that "magic" strings make me cringe a little but after dealing with distributed systems for a number of years and all the headaches around versioning and in place upgrades, etc... Even something as simple as an enum can be a real pain. I'm fine with the "magic" strings as long as their are nice abstractions on top of them. I would consider the "magic" strings almost like Assembly or IL, Wrap them nicely then you only rarely have to think about them.
Loved the talk but I was curious why not use something similar to ODATA URI\URL Conventions instead of just paths? That should still allow for a easy resource based caching strategy but with some more query ability other than just paths. What do you gain with just paths?