There are a few new concepts that need to be learned when beginning work with asyncio as well as some confusing naming choices (who would expect that a coroutine is not the same as a coroutine function?). Some of the tooling is also lacking. Armin points out, no doubt with a look at server frameworks, that there is no elegant way to access the context of a task.

That being said, as someone who started working with asyncio in Python 3.5 none of it feels particularly difficult to understand. Asyncio needs more work, sure, but the API so far is relatively straightforward.

The overloading of iterators/generators is a bit odd. But the same approach that was taken with JavaScript -- and it's nothing anyone working with Python 3.5 or above will be exposed to. If I recall correctly, Python 3.6 will even feature async generators. Any developers diving into this using that release won't have to ask themselves why they can't 'yield' from within an 'async' function.