Cat's out of the bag, may as well make public my experiment to enable WebGL on all webviews: https://github.com/rpetrich/WebGLEnabler
That's pretty neat! An unfortunate side effect is that running Mobile Safari unsigned negates the 'dynamic-codesigning' entitlement, which means that Nitro is disabled.
That said, a WebGL-enabled UIWebView running in your own app will also not be Nitro-enabled. I've run the PhiloGL spinning world demo on my device and it's running at 40fps, so simpler demos may be possible without a Nitro to boost things a bit.
I really wish I had a better understanding of disassembly.
The best resources I found are:
I'm really embarrassed to admit I have very little understanding of what happens below Objective-C. Looks like it's time for me to start reading…
You only need to look at the number of engineers Apple has contributing to WebKit & new web standards (CSS transitions & animations, WebGL etc.).
I strongly believe the whole HTML5 standard is supported on iOS5 but it has to be enabled. Did anyone notice the SQLite database that's created everytime you use a UIWebview? I've been trying to enable offline navigation and got kinda stuck but this gives me a couple of good new ideas.
There's nothing you have to do to enable it. Except use it.