I tested the nVidida extension demos some months ago. Even on my rather modest 650Ti it's super fast, drawing and transforming SVG images such as "the tiger" as if they were textures. With transparency and all, freely scalable, and antialiased. Super awesome.
The only thing that sucks about it is that it's not supported on any other vendor, and nVidia actually added way too much, so it likely will not ever make it into ARB or even core.
The extension supports not only rendering SVG paths, but also outline text, and some PostScript-like custom format, and it's directly programmable via a special API, too.
It would be cool if they'd just scratch 90% of that and keep SVG path rendering (or alternatively the custom format, which you can trivially generate from SVG), and it was made a core feature. But as it is, it's pretty useless, since you must implement your own SVG drawing anyway to account for other vendors. And since you have to do that, you don't need the extension.