I recently lamented the lack of general support for WebGL in Chrome. Here's what Mozilla says about the state of Firefox WebGL. Google says they are working on a software renderer for Chrome.
However WebGL reaches the masses, I have to say that it's not there yet. I'd consider it an early adopter technology at best. Would it have been better to focus on older OpenGL features to reach everyone today? Or is it better that they focused on the current modern, so that we don't regret old lock-in later? Whatever is best, I think WebGL will be safe to use for most of the web in about 5 years or so. I say five years because we need time for implementations to stabilize, support more drivers, use software rendering effectively, old computers to get replaced, and so on.
That's my guess. Five years. So 2016, I guess. (And I'm ignoring IE. I consider IE only as relevant as Microsoft wants it to be, by playing nice with everyone else.)
We'll see if I'm being too conservative.
But 2016 is still cool. Arbitrary 3D awesomeness. And I suspect JS will run very close to native speed by then, too.
What platform are you targeting for 2016?