Luckily they aren't stealing affiliate money from their users this time but 1) money is still being made off of our links* and 2) it's still a security risk and privacy concern. For more details see antumbral's entry here and shatterstripes's entry here. Those entries also detail how to protect links from yourself via Firefox's Adblock and the LJ Admin Console. Unfortunately it isn't possible to protect your links: every time someone goes to your journal or views your entry on their f-list, your links will be send to that third-party website. Boo!
* I am aware that LiveJournal is a business but these practices strike me as dodgy nonetheless, on LJ or elsewhere. If you don't have a problem with any of this, I'm happy to agree to disagree, as always. :)