If you use Google to search the Web, you too may have noticed that sponsored results have been taking over more and more of the search engine results page.

Don’t go looking too far if you want a reason for that: still, approximately 97% of Google’s revenues come from its core search engine advertising business (the company will release its financial results for Q2 2012 this Thursday).

But according to a search marketing advertising study carried out in the United States by Internet marketing software company Wordstream, the click-through rate or CTR of paid search ads on Google now even outnumbers clicks on “free” organic search result listings by nearly a 2:1 ratio for high-commercial intent keyword searches (that is, people clearly looking to buy something).

Wordstream has made a (hideous) infographic to accompany the results of its study, but we’ll refrain from reposting it in full here to spare you the eye sore.

For the record, unpaid organic clicks still account for the majority of clicks for searches conducted on Google, but we all know it’s getting harder to get exposure there as the company continues to crack down hard on SEO ‘spammers’ and increasingly touting a wide variety of paid alternatives to businesses looking to advertise online. But, Wordstream says, not all keyword searches are created equal.

googll Google ad clicks outnumber normal search results by 2:1 for some commercial keywords: study

Wordstream asserts that ads on Google are steadily becoming ‘bigger, more engaging and more targeted’, and found that particularly for valuable, high-commercial intent keyword searches, paid search ads gave the “free” organic search listings one hell of a pounding in terms of click-through rate.

words Google ad clicks outnumber normal search results by 2:1 for some commercial keywords: study

Makes you wonder if it’s still worth focusing on search engine optimization only when you’re actively trying to make people buy products online.

Oh, and also worth noting: Wordstream claims total click-through rates for Google ads on high-commercial intent search queries are up to 600 times higher than the average CTR for ads on a typical Facebook page. Would love to see more research there.