I registered for Facebook in January 2007. I can't find the exact date I asked to leave, but it was probably later that year, around October. Much to my surprise, Facebook had no way to actually delete an account, you could only deactivate it. That meant, you couldn't log in but your data, all photos, anything you'd ever posted was going to remain with them. I emailed Facebook about this and was told that it was "very complicated" for them to remove my personal data. "You might want to come back." I kept up a two-week discussion with Facebook which ended with them claiming to have removed all of my data, although I have no way of knowing this was true.
I believe today, three years later you can delete your account, although I still don't know what happens to your data. I do know that Facebook, while it may be fun and even useful, is not what I want. Without going into a point by point, I don't see the benefit of adding a stream of personal data to a corportate entity so they can make money (which they need to do to stay in business) by selling it to other commercial entities. I don't feel the distractions of popup suggestions as an advantage to me. I'd much rather have friends tell me specifically what they're doing, and discover things serendipitously by talking to people and using my own prejudices filters that give each friend a credibility weight.
Here is why someone else says he canceled his FaceBook account. Quote: "a large part of what I have to do on Facebook now is adapt to their changes on their terms. This is unacceptable to me, especially when I don’t see the website adding significant benefits."
As soemone who has followed technology since a very early age, I love the idea of always being connected to multiple streams of communication, yet a don't get a good feeling from Facebook. Quite the contrary, I see Facebook as a huge, very media-rich forum of the kind I abhor in the wine or tech world. I realize many people love it, including some who are far from newbies or technophobes. What I also observe though, is that the most clueless people I know are big on Facebook and they love friending a large number of people without regard to quality.
I think the number of very close friends, the ones you'd do almost anything for, can be counted on the fingers of one hand. The next wave might have between 10 and 50 people you know well. When tese numbers get into the hundreds and thousands, it isn't Dunbar's number that worries me, it's the fact that it becomes CRM or in this case ARM: Acquaintance Relations Management.