Emscripten certainly should benefit from value objects because they are required to deal with 64-bit integers and 32-bit floats efficiently.
Supporting asm.js as a compilation target for managed languages is very much a goal (according to the FAQ anyway), including binary data and somehow garbage collecting the same within asm.js. I think this includes JSIL eventually, but it doesn't really matter whether you call it asm.js or not: those features fall under the general umbrella of things that are only necessary for compiling high performance, statically typed code to JavaScript, which would become a fairly unimportant use case if the "correct way" to run such code was via PNaCl; thus, they can be considered a parallel technology stack to PNaCl. I personally think that since it's still a way smaller stack and for other reasons, JavaScript is the better approach, but I don't agree that this is all stuff that is orthogonal or going to be done anyway.
Supporting asm.js as a compilation target for managed languages is very much a goal (according to the FAQ anyway), including binary data and somehow garbage collecting the same within asm.js. I think this includes JSIL eventually, but it doesn't really matter whether you call it asm.js or not: those features fall under the general umbrella of things that are only necessary for compiling high performance, statically typed code to JavaScript, which would become a fairly unimportant use case if the "correct way" to run such code was via PNaCl; thus, they can be considered a parallel technology stack to PNaCl. I personally think that since it's still a way smaller stack and for other reasons, JavaScript is the better approach, but I don't agree that this is all stuff that is orthogonal or going to be done anyway.