Norton Secured (OK) vs (OK)

I have my web site set up with the

<meta name="norton-safeweb-site-verification"  etc. etc.

And when you search for my site, you get the nice friendly green dot (OK).

And I see this for many other sites.

 

However, some sites, like Amazon.com, have an even cooler logo shown in the Google search results - those sites are marked with "^Norton Secured" as well as the nice green (OK) dot.

 

What's the difference?  How can I get the even better certification with the nice logo?  What are some of these other sites using?

 

Thanks

-Dave