[coldtea]

>I'm interested, why does SVG seem to de the default choice for web graphics?

Because SVG IS web graphics (emphasis on "web"). It lives on the DOM, it's objects have event callbacks, can be styled in CSS-fashion, have nested items, links, etc.

In contrast, Canvas is just a bitmap pane that you can draw own in an imperative way through a JS API -- and everything above that has to be programmed by you or a third party lib in an ad-hoc way.