Is there any proposed timeline for a stable release? Big features like the recent async IO shows the language is very unstable right now.
nitpick: The language is pretty stable, what changes is the standard library.
Andrew's take is "it's ready when it's ready but we hope it's good enough before it's fully ready that you want to use it anyway".
It's different and I like it. You get one shot at it and may just as well get it right in as many areas as possible.
There is no ETA on 1.0, but breakage has followed the pattern of it not really being hard to upgrade to a newer version, as it is very well documented on the version release notes.