Last week, Facebook revealed their latest tool to help webmasters “Socialise” their sites – Facebook Open Graph.

Open Graph is Facebook’s latest foray into search engine functionality and if all else fails, it’s best to think of it simply as the first step towards a social search engine. Facebook is hoping that as people browse the web they will “like” pages by clicking a Facebook button which then informs their friends via Facebook.

Open Graph will enable sites which you’ve never been to before display recommendations and information tailored for your tastes based on what you or your friends have previously “liked”. At surface level then this is just a slightly more powerful version of those buttons you see around the web which enable you to share stuff you like with your friends. But the story of Open Graph is going to be so much more than that.

Facebook already have access to all sorts of personal information about you: your key demographics; your likes; your dislikes; what your friends like; when you last clicked a brand advert on Facebook.com and so on. With Open Graph they will also start to collect data about your browsing habits enabling them to build a much more comprehensive profile for each of their users.

If Facebook overcomes the row about its privacy terms and conditions, this will give them all the data they need to offer highly targeted advertising campaigns.

It is this that is making Google pay attention. Paid advertising was worth $22bn to Google in 2010 and although their search data enables them to sell advertising based on keywords and location, they are as yet unable to sell based on personalised data such as recommendations or browsing history.

Facebook on the other hand are starting to build exactly this system. Their “social” search is going to give them the data to personalise the web in a way never seen before. For example – a user “likes” a page on a website which has information about Panasonic LCD TVs. A friend of theirs then starts browsing a second website looking to buy a TV. If Facebook get their way, this friend will see a featured link for Panasonic LCD TVs at the top of the page with “Gary Newman likes this” underneath.

Would this influence him to buy the product? Who knows, but Open Graph could be set to change the landscape for online advertising.

Dare I say it, but you can try the “like” button right underneath this article. We promise not to sell you any TVs…