I’m still blogging after more than 5 years. I recently re-joined Linkedin’s Linkedin Bloggers group as a moderator after Des Walsh, Robyn Tippins, and I decided to migrate away from our moribund Yahoo! group of the same name.

Joining the Linkedin Bloggers group was one of the things I did after I seriously started using my blog to publish professionally interesting items. My first published blog item was Identity Theft and the Licensing of Personal Information.

That reflected my interest in the intersection between intellectual property rights and personal information. That led to my interest in the issue of “data portability” and the ability people have to manage how personal infromation is shared across different networks.

Like many people I have a variety of personal and professional interests. As a result I “engage” online with a variety of different groups and networks. I now use my blog as one of several different online locations, each of which has a somewhat different focus. The differences among these different engagement locations (blog, Posterous, Facebook, Twitter, Linkedin, etc.) and their associated “communities” have raised in my mind questions about the need and desirability for data portability of “friend” information across sites.

I’ve come to believe that making it easier to share “friend” information across sites really provides more benefits to marketers and advertisers than to individual professionals such as myself. Here’s why.

First there are different types of “friendships” such as business, purely social, family, internal to company, external, etc.

Next, these friendships can change in an instant (“oops - she just got divorced.”)

Then there is the question of relationship strength, e.g., a casual friend known only because you’re both interested in researching the same product purchase, vs. someone you’ve known and loved for over 20 years.

Trying to keep all these straight across different platforms that exchange data is not just a logistic but a technological challenge. Add to this the fact that all some advertisers want to do is to get the largest number of exposures possible for a particular message without caring about such subtleties, and you can easily end up deciding, as I have, to publish and interact in a variety of different communities. (Besides, you never know when your personal information will be “leaked.”)

This is also why I rarely include the feature on one platform to auto-message or auto-update other platforms; I tend to use Twitter and Facebook differently so I don’t automatically post one’s message to another - I prefer that to be a conscious decision. (For more on this topic see Robo-Tweets and the Internet of Things: A Survey.)

I also “unfollow” people on Twitter who start auto-tweeting their physical location via services such as FourSquare; that’s just due to my preference to engage online with people, not their electronic avatars.