I'll rephrase: why is any new VM to be relegated to the OS? The presence of incumbent VMs?
JS is an incumbent. Pepper is similar to nsapi, and has nice features which are compatible with HTML5's implementation (as in canvas). Saying it shouldn't be adopted because Nobody is adopting it is circular.
I said clearly why Pepper is not being adopted: it is a gigantic pile of API and implementation specified only by the C++ in chromium.org svn. Other browsers cannot port all that OS and WebKit glue code except at very high cost, direct and opportunity -- and even then on a bet that Pepper + NaCl wins, and again on a treadmill far behind Chrome.
Do you actually work on a browser codebase? If so, have you worked on competing browsers' codebases at all? Do you begin to see the problem? It's not quite Active X (open source is a small help), but it's on that slope and uphill only a bit.
> Other browsers cannot port all that OS and WebKit glue code except at very high cost
Why would any other browser need that glue code? The Pepper API is large but fairly straightforward and doesn't change dramatically between revisions. In addition, I don't believe Google has ever said that they wouldn't make the development process around those changes more open (at least making them public before pushing the new implementation out to the world).
> Do you actually work on a browser codebase? If so, have you worked on competing browsers' codebases at all? Do you begin to see the problem? It's not quite Active X (open source is a small help), but it's on that slope and uphill only a bit.
I've only worked on Webkit a small amount (mainly doing security analysis) but I worked with Pepper a good deal and I've worked on Gecko for a decent while now. I really don't see the incompatibility; there are plenty of good arguments against NaCl, but I don't think there's a fundamental problem there. I can definitely understand not wanting to allocate resources to the issue, but not being opposed to the issue in general.
> Why would any other browser need that glue code?
Because other browsers do not use WebKit, or at least chromium WebKit. Are you really asserting that no glue code is required on any other browser?
> The Pepper API is large but fairly straightforward
Where is the spec? You are not in the real world here.
There are plenty of differences between Gecko's audio APIs and Pepper's. If you really work on Gecko, mail me about this. I have reason to doubt your claims here.
JS is an incumbent. Pepper is similar to nsapi, and has nice features which are compatible with HTML5's implementation (as in canvas). Saying it shouldn't be adopted because Nobody is adopting it is circular.
What are old-style plugins? Anything not JS?