Specify your canonical at the site level

Carpe diem on any duplicate content worries: we now support a format that allows you to publicly specify your preferred version of a URL. If your site has identical or vastly similar content that's accessible through multiple URLs, this format provides you with more control over the URL returned in search results. It also helps to make sure that properties such as link popularity are consolidated to your preferred version.

This is great. Google is giving web developers much more control over sites that they push out. No longer do you have to go into Webmaster Tools to fix canonical issues with your website.

Actually, this method gives you much more control. In summary, you can have duplicate content on your website and specify, through a special tag, which is the page that Google should be indexing. This means you can easily filter out Print version of pages or pages with additional query parameters.

Link:
http://googlewebmastercentral.blogspot.com...