What started out as a small beta test one year ago has been rolled out to all Adwords advertisers.  The new interest categories allow advertisers to target their audience, based on interests and demographics. 

So, how does it work?

When a user visits a website, Google’s system looks at the page type and frequency of visits, then associates the user’s browser with the relevant interest categories. Provided the sites they visit have AdSense, you will be able to show adverts to your audience wherever they are surfing on the web – it is no longer limited to contextual or topically relevant content or themes. With over 1,000 categories & 500 million interested users, there is bound to be an option for your business. 

If you are interested in giving it try, it couldn’t be easier. Go to the Audiences tab and you will be presented with a list of interest categories to choose from along with the estimated amount of searchers by category: 

As always, you only pay for clicks or impressions at auction prices.

Google have provided a best practices guide to help you get started.