I'm not sure if this goes here, but...

[justgoto]

Facebook's Beacon service turns users into living ads, but at what cost?

On November 6, Facebook launched an advertising system called Beacon that consists of a partnership between the popular social network and 44 other sites. The system allows a user's activity outside of Facebook to be recorded and then posted on his or her news feed

Comments

[kali921]

Question from the floor: is this something that the user on Facebook opts into autmoatically, or do you have to opt out of it to get away from it?

[estelle]

automatic turned on function from Facebook's side but LJ announced that you'd have to enable it first.

FAQ: http://www.livejournal.com/support/faqbrowse.bml?faqid=279

[donutgirl]

I don't understand -- how can facebook automatically pick up my LJ posts when I never even told them I have an LJ? I mean, my LJ isn't so anonymous that a private eye couldn't figure out who I am, but how would a bot know the two are connected?

[estelle]

They know who you are because you log into your account.

Site X who partnered up with Facebook checks if you're also logged in facebook and/or have their cookie. If you are, they send info about your activity on their site to Facebook
Facebook publishes the info about your activity on Site X on your Facebook minifeed.

Not all of the Websites in the above post send info about your activity to Facebook automatically. LiveJournal thankfully does not send it automatically, you'd have to opt in.
But they could.
And if you use any of the other sites and do not want your activity to appear on Facebook you should opt out your Facebook account or block beacon on your computer.

[donutgirl]

Eek -- that's really shady. Thanks for explaining it to me. Luckily I don't use any of those sites except LJ, but the whole idea skeeves me out.