[jokoon]

So does it just do what NaCL was already doing, or at least is the objective the same?

I'm more worried about more specific things like hardware access (GPU, mouse inputs, networking, windowing)

It seems wasm runs at native speeds and take full advantage of optimization, but can it really be a solution fits all? There must be some things wasm can't do. And so far, since JS did almost everything, I don't see the point of wasm if it can't do what other language can.

[azakai]

The main difference is that NaCl used a plugin API (PPAPI). WebAssembly, like asm.js, can access JavaScript, and so it has indirect access to DOM APIs, with no new powers over the existing web.

The main point of wasm, from my perspective, is startup speed. wasm will allow much smaller downloads of large codebases, and much faster parsing (due to the binary format). For small programs this might not matter, but for big ones, it's a huge deal.