>
> This is very nice and works well for me.  I would very much like to see
> that in orgmode.  Thanks a lot!
>

Great, I've just committed this patch.  Thanks for your original example
which this simply extends.

>
> How do I extend your example to output latex for latex, svg for html and
> png in all other cases?
>

The attached does this.  The catch is that the :imagemagick header
argument is required for png (and other) image types to be used.