Looks like there is evidence that the next version of Google Maps will use SVG for capable browsers (Firefox 1.5 and Opera 9, currently).  Currently Google uses Microsoft's VML for Internet Explorer and transparent PNGs for other browsers to display driving directions overlayed onto the map.  Using SVG on the client side would prevent the current server-client roundtrip that needs to happen to provide transparent PNGs.

Of course, this is a tremendous vote by Google for SVG technology in the browser.

More details with links provided here.