If you don't need VML and IE8 support then use Canvas (PaperJS for example). Look at latest IE10 demos for Windows 7. They have amazing animations in Canvas. SVG is not capable to do anything close to them.
Overall Canvas is available at all mobile browsers. SVG is not working at early versions of Android 2.0- 2.3 (as I know)
Yes, Canvas is not scalable, but it so fast that you can redraw the whole canvas faster then browser capable to scroll view port.
From my perspective Microsoft's optimizations provides means to use Canvas as regular GDI engine and implement graphics applications like we do them for Windows now.
