Except it just got a garbage collector.

We're working to make sure that there will be an officially blessed subset (called a "profile") that will not require GC.

I'd be interested in knowing more about that. Is there a summary of current progress anywhere?

This is the repo for the "profiles" feature by which we will define standard subsets:

https://github.com/webassembly/profiles

It did? I thought that proposal was basically stuck; I haven't checked in a while, but I haven't heard of it moving forward either.

Chrome will be shipping it in the next version: https://chromestatus.com/feature/6062715726462976

Which makes it an even better compilation target!