Is this really a surprise? People visit social networking sites for contact, not content. It's no surprise that traditional online advertising isn't effective there. Neither is the massive rush and gradual decline in general visits, as Techdirt sums up nicely here: [www.techdirt.com]

Nick, sometimes a cursory look at the statistics doesn't reveal the whole story. In particular, I'd caution in reading too much into declines in average engagement for sites that are rapidly expanding their visitor base.

Why? Because new users = light users. It's quite possible -- maybe even likely -- that the longer tenured users have the same (or higher) engagement as before, but the newer users are bringing down the average.

On the subject of online advertising, we (comScore) released a study today along with Starcom and Tacoda showing why clicks are an often poor measure of display ad performance. The brand-building effect of display ads often goes overlooked, but is usually more important than clicks.

[www.comscore.com]

Andrew Lipsman, comScore

The rate of increase on spam content is directly proportional to the decrease in returning visitor activity.

Facebook is slowly becoming a joke. Every time I log in I have a dozen invites to participate in polls or answer silly questions by my "friends"

Oh dear God, Facebook is so annoying now that both apps have appeared and that there is open enrollment to anyone. It isn't some miracle website, it was just a fun one to dink around with friends on. Now the fun is gone.