NEW YORK (AdAge.com) -- How many visitors a website gets matters, but so does the amount of time people spend on the website. And in that category, Facebook is smoking the rest of the big guns.
Users spent an average of five hours and 12 minutes on the site in July, according to Nielsen -- that's up from just one hour and 30 minutes a year ago. The next-closest of the giant web properties: Yahoo, at three hours, 23 minutes; followed by AOL (two hours, 36 minutes); Fox Interactive (two hours, 19 minutes); and MSN (two hours, eight minutes). Who ever said portals were dead?
One explanation for the growth: The network effect. As Facebook's audience has ballooned, there are more people on the site for any given user to connect to, play games with and comment on, making it more useful and entertaining and increasing the amount of time each user spends on it. It also helps that Facebook has managed to maintain frequency of use.
"A couple years ago, about half of our users logged onto Facebook every day, and as we've grown to 250 million worldwide users, that number hasn't changed," said Mike Murphy, VP-global sales at Facebook. "It makes it more engaging from a user standpoint and we get more minutes spent, which means we have more opportunities to show more people an ad message in a given day."
That, he said, has allowed the site to expand the number of big advertisers it works with. Right now, 83 of Ad Age's 100 Leading National Advertisers are on Facebook.
Time spent is increasingly important as a site saturates the online audience. The law of large numbers means it gets harder to grow by just adding new users, so it's important to grow the amount of time spent and mind share among existing users. Today, Facebook is the fourth-largest property in terms of unique visitors, with just shy of 97 million monthly unique visitors, behind Google, Yahoo and MSN/Windows Live.
Time spent is an increasingly important way for media buyers and planners to gauge a site's importance and influence on people, said Rachel Ooms, VP-group media director at Moxie Interactive.
"Buying media is about targeting mass audiences and it's about where people are flocking. If people are there, we want to be there," she said.
Added Rick Gardinier, chief digital officer of Brunner: "Unique visitors or banner-ad click-throughs are just one piece to the puzzle. We're starting to look at engagement and time spent in rich media or in specific content areas. Those are sometimes more important." However, he cautioned, just because people spend a lot of time on a site doesn't mean they're in prime ad-reception mode. And that can occur with social networks.
Still, from Facebook's standpoint, the more time people are on it, the more time they will have to see its homepage ad, which is a key part of its monetization strategy. That equation -- more time on a website equals more opportunity for exposure -- has inspired some web sellers to recast their sales models to sell on time-based metrics. Betawave, under CEO Matt Freeman's direction, is aggregating sites that command attention, using time as a proxy. And VideoEgg has been marketing its network based on the idea that attention to an ad is what really matters. Time is an essential component of that.
"Most brand-building environments have historically been about taking discrete pieces of consumer's time," said Videoegg Chief Marketing Officer Troy Young. "So how do we make internet advertising less about traffic generation and navigation and more about time?"
Incidentally, Facebook commands a lot of time -- the most of the 20 largest sites -- but it's not the biggest time suck on the web, according to Nielsen. Among sites with more than a half-million unique visitors, Blizzard Entertainment is tops, with almost 24 hours a month, followed by an array of other mostly gaming-related sites. Facebook ranks eighth.
Not every site wants people to hang around. Google, for example, has for years talked about its goal to get people to what they're looking for fast. In fact, Google's Marisa Mayer has said a page-load delay of 400 milliseconds can translate into a 1% drop in search query volume.