It's still not ready for general usage. On real-world codebases it has correctness issues that need to be sorted out, and there are missing features like longjmp and C++ exceptions.
Just like other components of the technology preview, I think it would be useful to have interested developers try it out and give feedback in the form of bug reports -- understanding that things are incomplete and going to change.
I'm sort of holding back at the moment until emscripten has everything integrated to build wasm binaries, even if it is not the final LLVM backend. But I can't wait to flip the switch on the wasm builds :)
BTW We're happy that we got some of your demos into the build-suite, but unfortunately we can't run them anymore. The binaries there are still version 0xA and the .wast files have some errors that prevent translating them to 0xB with the sexpr-wasm tool.