what makes sns sticky?

MySpace reminds me so much of a fair midway, it is an unrelenting assault on my senses; it is visual chaos, flashing lights, spectacle often without substance. In fact, the only thing missing is odor. (perhaps there should be a parenthetical addendum of so far). The fact that it's sticky just completes the image.

However, thinking about why social network sites attract and retain visitors, a couple of questions come to mind........Is it the content? Is there something about members and/or visitors that makes them more likely to get stuck?
Yes, and yes.

Visitors return because there are new things to see, there is a dynamic quality to personal pages, reflecting shifting moods, new interests, events, and fluctuating favorites and dislikes, compounded by how interactive having friends and belonging to groups can be. Of course, all of this presupposes that members are spending time updating, creating and bolstering their presence, adding and interacting with friends and groups.

As to commonality among users, I think by virtue of the fact that people go to these sites either by invitation or their own prerogative, and reflecting on boyd & Ellison (2007), the networks parallel users more 'real' lives, "primarily communicating with people who are already a part of their extended social network."; the sns is not the fundamental link between users, it is the medium.

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as for myself, sns are kind of an interesting phenomena, and while I am all over social software tools that make work easier and more efficient, I am not looking for ways to substitute the virtual for real contact in my personal life. And to that end, of the social networks I tried, I liked Ning the most - I found a whole lot easier to navigate and understand, visually it was less confusing.