As long as you can turn on ligatures in your font rendering API per-platform, this is a fully cross-platform solution to graphing, in a font file.
(Using printf's, basically, to do complicated graphs - absurd and awesome!)
Hinting and the Web
Webfonts are not currently offered.
I understand that there would be advantages with a high resolution display. It would scale automatically. Anything beside that?
Subpixel rendering is, of course, very helpful. It's really preposterous though that we have to resort to abusing fonts to get subpixel when implementing it for arbitrary vector rendering is so straightforward.
The other big problem with using fonts for hinting support is that people have differing opinions on the value of hinting for fonts, but everyone would probably agree on the value of hinting for icons. If you disable hinting because it hurts your eyes (or because you use OS X and don't have a choice), then you're going to miss out on icon hinting as well.
Seems to me what we really need is a client side solution for rendering arbitrary SVG with either manual hinting or icon-optimized autohinting (which might be too general of a concept to be doable).
You can sprite SVGs, but you have to maintain it just as you would have to maintain a sprite of PNGs. The only advantage being that a sprited SVG would scale to a HDPI monitor without needing a second set of higher resolution images.
I ended up going with icon fonts because it requires significantly less CSS than dealing with the position of an icon in a sprite. I actually find it is easier to maintain since I can style icons with shadows, opacity, color, etc.
One drawback, using icon fonts generally means having flat icons. You can't have fancy 3D-like iconography.
Plus, icons are easier to handle as a regular text/font asset, than as SVG, and you can use all the tools available for web typography for them.
That said, why we never had a simple vector _IMAGE_ format for the web is beyond me.
That would be dead easy to add support for, compared to SVG (just treat as any other image format) and it would handle lots of use cases.