I remember looking at that matplotlib page for the first time and coming away thinking those graphs look a lot better and sharper than the default R ones. However, I found the reason for that is the images on that page are quite high resolution PNGs. If you make graphs of 200dpi or more in R, they look equally good. The annoying thing though is that you have to adjust all the margins and character size settings in R to plot at a higher resolution.

Well done sir, you've just made me take the time to install Mayavi. (There were even a bunch of packages I had to unmask in Portage to do it.)