LinkedIn
My biggest gripe with LinkedIn is that recently, I made the fatal mistake of letting it look at my Gmail contacts. Getting suggestions for contacts who are already using LinkedIn was the intention but they <i>invited</i> anyone who had ever mailed me!<p>Up until that point, my contact list was limited to people that I personally knew and could recommend. Now, months later, I am still getting successful "contact accepted" replies from people that I barely know. I.e everyone who ever contributed to any mailing list that I was ever subscribed to.<p>I even got replies from people asking why I contacted them. I have no idea how many people remain to accept my invitation or even who they are.<p>What a disaster. It has changed for me, an early user of the site, what was a useful database of the people I know, to now some random connection of strangers.<p>The worst part is the link to connect to Gmail still appears and I'm sure that it doesn't clearly indicate what it's intention is. So, if you have connected with an email provider in the past be wary of allowing it to connect again.<p>And yes, if you let any site connect to your personal data, expect the worst outcome...