Consumers care about car internals at anything more than a superficial level?

If HTML5 is actually important to improving the end-user experience, if browsers that implement it have a real, demonstrable advantage over those that don't, then it doesn't matter if the consumer cares about HTML5 or not. They'll still want the results that technology enables.

Absolutely consumers care about the car's internals. Most people know a lot more about their cars than about web standards.

Right, the typical consumer can crank out exactly which relevant industry standards their car's internals adhere to.

When consumers say they care about the internals of their cars, what they actually care about are things like power, fuel efficiency, torque, whatever. They have nothing more than a superficial understanding of how the actual mechanics of the vehicle translate into these qualities. Talking about V8 engines, etc, is, for the typical consumer, nothing more than marketing.

HTML5 could certainly be a marketing device (5? That's one more than 4, it must be better!), especially if you showed end users cool things that web sites can do with HTML5 that they can't do with 4.

I think that's where we disagree. I haven't come across any normal folk who even remotely cares about HTML version or javascript library, etc. I have however come across many people from various backgrounds talking about how different cars perform.

edit: ultimately we'll probably need some numbers to back our claims. I've got way too many bugs to fix to do any significant digging. But I'm open to counterexamples if you can find some numbers.

You've never heard anyone complain that a particular page looks weird, or that it loads or runs really slow? You seem to mixing up the levels of abstraction as we cross the boundary moving into the car analogy. Cars have industry standards, too. Nobody knows shit about them. But they still care, indirectly, because adhering or not adhering to those standards affects in some way the experiences that the end users do care about. That's the only point I'm making. If you actually disagree with that, I'm really surprised.

I'm disagreeing with the degree of care. I don't think most people give a hoot about web standards. I do think most people care about their car standards/internals.