It would be possible to leverage a simple machine code verifier similar to NaCl's in a WebAssembly backend. Nobody does it right now, but there's been some work on taking WebAssembly as input to their Subzero PNaCl->NaCl compiler.
Another factor is that these consumer Optane products only have 1 or 2 chips to multiplex operations across. Their enterprise product, the SSD DC P4800X uses 28 of the same 16GB chips and can read or write at ~2GB/s which is competitive with NVMe SSDs.
Not exactly. Node.js will probably integrate a future release of V8 that supports WebAssembly, and WAVM isn't a suitable replacement for that.
WAVM is more like V8, but for WebAssembly only instead of both JavaScript and WebAssembly. The purpose is to serve as a simple VM for my programming language that compiles to WebAssembly.
WebAssembly definitely benefits from being able to avoid the JavaScript garbage collector.
I'm working on a garbage collected language that will use WebAssembly/WAVM as that backend. It's possible as-is, but may require some non-standard extensions to get good performance (e.g. to find GC roots on the stack). I'll certainly contribute anything I do there for standardization, but I suspect the WebAssembly committee will beat me to it.