This Mediaweek article points out how page views on social networking sites might not be as important to advertisers as they are on, say, a regular portal such as Yahoo. Social networking users tend to spend more time and view lots of pages while on these sites, meaning that the actual number of unique visitors isn't as high as it is with other sites.

Plus (and we tend to agree), social networking users probably aren't in the mood to view ads on these sites. Not that people are ever really "in the mood" to view ads at all. But if you're actually *doing* things - updating your profile, writing to friends, sharing media, and so on - you're less likely to look at ads as you are while surfing the Web in a more general fashion.

We can't help but think this has some relevance to mobile users. Anyone who flips open their cell phone to read a quick article or watch a video clip likely doesn't have the time to check out advertising, even if they're really interested in it. This mindset could present quite a challenge to media companies as the mobile media market expands.

IQ Report: Why Connecting Matters More Than Page Views on Networking Sites [Mediaweek]