How does WebGL achieve such high quality rendering?

I am starting to look at WebGL and the first thing I noticed is that the rendering quality of graphics inside the browser is of a very high quality and that this does not appear to come at the expense of performance. In my own OpenGL C or Java applications I am unable to achieve such high quality rendering either by specifying the number of samples or by manually fiddling with the NVIDIA driver antialiasing settings in the Control Panel (on Windows).

So, how does WebGL achieve such high quality rendering? It seems to be completely independent of the driver settings and looks crisper than any application that I have seen running on the desktop. Ideally I would like to use the same techniques (antialiasing?) in my own non-web applications.

Screenshots for comparison ?
Because I find that surprising.

Here are some screenshots from the Google WebGL samples. The quality of rendering shown here is much higher than I have been able to achieve in my own desktop OpenGL applications.

Why? What secrets is the browser using (Firefox in this case)?

I have that problems not.