It's not 100% for sure, but it's 99% for sure that async/await will be stable in August. The decision to stabilize is being made in seven days, and if it's decided, it will take that long to make it into its first stable release.
We have the whole team waiting for this to land. We're probably going with nightly already due to the problems fitting Futures 0.1 model to our codebase.
I've been trying a couple of approaches already, but first we're aiming correctness and after that async/await.
Many libraries use tokio::spawn behind the scenes, so it seems we need compat from 0.1 to 0.3 and back to 0.1 to get old futures to work with async/await and the resulting futures to work in 0.1 tokio.
Last time I checked the async/await feature in tokio had some weird crashes and tokio::spawn crashes when used inside romio...
