Todd

I like this option I stumbled accross.

add modernizer.js

add this to your html:

        if(!Modernizr.svg)var i=document.getElementsByTagName("img"),j,y;for(j=i.length;j--;)y=i[j].src,y.match(/svg$/)&&(i[j].src=y.slice(0,-3)+"png")
</pre></code>

Then have your .svg and .png backup file called the same name!