The latest news in online display advertising is that ad clickthrough rates have now leveled off after an extended period of decline – one that was exacerbated by the economic downturn.

So reports digital media marketing firm MediaMind (Eyeblaster). According to a report released this past week, one key reason for the decline being arrested is the greater sophistication of advertisers in targeting online advertising to audiences and groups that are more likely to be interested in them.

That being said, the overall clickthrough rate has leveled off at an abysmal 0.09%.

That is correct: less than one tenth of one percent. In any other business, this would be a rounding error.

If that statistic seems difficult to believe, consider this factoid: The average Internet user in America is delivered more than 2,000 display ads over the course of a single month. We might think that users would be inclined to click on more than just two or three of these ads during a month’s time.

But it’s important to realize that when users are in the mood to shop and buy, they’re typically going straight to the sites they like … or they’re using Google, Bing or some other search engine to find their way.

And it turns out there’s really no such thing as an “average” Internet user, anyway. Research conducted by digital marketing auditing and intelligence firm comScore, Inc. has found that around two-thirds of people on the Internet never click on any display ads during the course of a month. Moreover, only 16% of Internet users are responsible for around 80% of all clicks on display ads.

All the more reason why search marketing continues to be the online advertising powerhouse that it is. And why not? It’s putting your business in front of the customer when s/he is in “search-and-buy” mode … not when s/he’s doing something else.