So what remaining problems with NaCl's compile-once-per-each-architecture model do you believe can't be solved by the combination of multi-architecture compilers (llvm, gcc ...) on the developer/server end and PNaCl on the client? Obviously the implementation is incomplete and immature, but Mozilla and Opera aren't even pretending that their opposition to NaCl is based on the immaturity of the implementation.
> And whatever benefits an Open Web, Mozilla will inevitably support, as it sustains their business model.
Mozilla inevitably supports and benefits from an Open Web only to the extent that you accept Mozilla's rather Newspeak definition of the Open Web as "a Web whose client API and runtime is under the shared control of a small group of browser vendors". If you have a less Orwellian kind of openness in mind, then it's clearly not true: Mozilla benefits from its shared control over the Web platform in largely the same way that MS benefits from its control over the Windows platform, and just like MS it has a strong self-interest in not seeing its platform "commoditised". As if that weren't perfectly clear already, then Chromeless underlines it. I assume you accept that Mozilla has a self-interest in seeing Chromeless succeed? The reason that Chromeless has a chance of hitting the big-time on the desktop is almost solely because Javascript and friends are popular on the Web client, and the ultimate reason for that is because JS and friends are bolted in and difficult to avoid on the web client.