So yesterday I received the usual web 2.0 "Your friend wants to connect with you to swap tips on styling your hair" type email. This time it was from TripIt. I ignored it, I’m social networking fatigued anyway, but sharing when I am away from my house strikes me as a bad idea.

Nothing new there until this evening. When I got another invitation, from someone else. There was an optout link, so I went to follow it. This presented a problem; it asked me log in. "Why?" I thought, "I haven’t signed up." So just to check I asked for a password reset and it worked. This was strange. Even more interesting when I reset the password for the account I never signed up for I discovered I had 3 invitations from yesterday and one from today.

What appears to happen is as soon as the first invite is sent TripIt creates an account on behalf of the recipient. That account is then searchable; today’s inviter said that when he searched for me the site said I was a member. So much for "registration is optional" in their privacy policy.

I wonder in the search for venture capital TripIt are using their user numbers; because I should not be a user.