People around the world have spent 9,305 years on YouTube since the site's inception, according to The Wall Street Journal writer Lee Gomes. Because YouTube tells us almost nothing about its users, he did a "scrape" of the site, which means he used a computer to methodically gather bits of public information scattered around a Web site in order to describe its usage in depth. This is legal, by the way.

So, what else did he find?

About a month ago, there were 5.1 million videos on YouTube; by the weekend that number had grown 20 percent, to 6.1 million. Gomes also found some of the most popular search terms are "love," "music," and "girl"; there are no less than 2,000 videos of French soccer star Zinedine Zidane's infamous World Cup Final head-butt.

"For all the talk of the Internet fragmenting tastes and interests, YouTube is an example of the Web homogenizing experiences," he notes.

He's absolutely right, but in a democratized kind of way: No one on YouTube decides what's funny or interesting for you. YouTube videos take up an estimated 45 terabytes of storage--which is about 5,000 computers' worth--and require several millions worth of bandwidth to transmit. No wonder the site still subsists off venture capital money.

Now marketers, pay attention: 70 percent of YouTube's users are American, and roughly half are under 20. These stats may not be all that surprising, but they drive home the point that teens and 20-somethings are spending considerable time at sites like YouTube and MySpace these days.