Developers that are fluent with the technology are going to be in high demand once more people know what you can do & stuff like this is what everyone wants.
Mobile devices don't yet support WebGL either. If you want to do 3D on mobile you have to use CSS 3D Transforms (not supported on some platforms) or Canvas Context2D with a "software" renderer (slow).
They will soon enough. If you start any substantial project now, by the time you finish WebGL will be available on most high-end phones, at least on Android.
Btw. the Nokia N900 has had WebGL support for a year or so. Too bad it's not a very popular model.
Developers that are fluent with the technology are going to be in high demand once more people know what you can do & stuff like this is what everyone wants.
Time to get reading!