In practice, those of you who have been waiting for the API to be published to write a plugin or an extension can start poking around. Use however only those things described in the documentation. We will not fall into the same trap Yum did in maintaining every class and every method that was ever declared in the code. On the other hand, if it’s in the docs it’s guaranteed to stay there with the same semantics or be duly deprecated. If it’s not in the docs and you need it, give us a holler.
Edit: Here’s the F20 update