The New York Times reports that Google is buying DoubleClick for USD 3.1 billion. That’s twice as much as Google paid for YouTube last year.

DoubleClick is one of the worlds leading online advertising companies, covering areas like display advertising, advertising optimization, rich media advertising, search and affiliate marketing.

This should be a good match for Google, who can benefit from DoubleClick’s network of advertisers and publishers as well as the company’s technology. Google is already a master of pay-per-click advertising. Now it will also get a hold of the rest of the online advertising scene.

It is easy to forget that from a revenue and sales perspective Google is first and foremost an advertising company, and not a search engine entreprise. It is the ads that bring in the money.

Microsoft has understood this. It has also been trying to get hold of Doubleclick, but lost in the final round.