Profile pictures matter. The site feature that attracted most attention on Klout, Facebook and StumbleUpon was the profile photo.
Job title garnered more attention than profile photo on LinkedIn. In fact, it got more attention than anything else on the page.
Who you know gets noticed. Even if for no better reason than their placement on the page, people do look at those little thumbnails of friends that appear on many social profiles. You can see this in the data from the Facebook, Google+, Twitter and Klout profiles.
Content on top wins. The further something is down a page, the fewer number of people look at it. This was true on both content-focused profiles such as Pinterest and Digg as well as socially focused profiles such as Facebook. On the Twitter and YouTube profiles, the effect was less extreme.