I came across the following infographic from Pew Internet. It illustrates the information that people believe they've shared online:
Though the data was collected in 2009, it's worth considering as we are still navigating issues of reputation management and digital identity. The information suggests that people are cautious about sharing personal media files (e.g., photos, videos, and personal opinion pieces), but are willing to be linked to employers/organizations—perhaps as a means of establishing authenticity and building reputation? The data sample are online users, so I would assume that this group is minimally aware of the importance of controlling the information connected to your Google search.
Naturally, the "Don't Know" column holds special interest, but that email addresses lead the category is not at all surprising. Email addresses are collected by virtually every online service, and increasingly many offline businesses as well. This seems to be the piece of information that may most easily slip from the user's control. I did find it interesting that even among this group the percentage of people unsure whether media images of them are available is lower than the percentage of people who are unsure whether home address and telephone numbers are available. I'm curious whether the "Don't Knows" are a subset of slightly less tech savvy users—if so, it's interesting that even they have given thought to the ways they are represented by media.