About all this frienditto crap, I will be blunt: the biggest reason you'd use a service like this would be to sabotage somebody by making their friends-locked posts public. That's the only possible thing a service like this would be good for, ultimately--and if you're planning to be one of the saboteurs, it's not like you're going to announce it, ala, "Yes, I plan to use this, so defriend me right now!" Yeah, right.
The moral of the story: if there's somebody on your friends list that you don't trust with your privacy, or moreover, somebody on their friends list you don't trust, there's only one thing to do. And that is, ultimately, this: don't say anything on LJ you wouldn't, ultimately, be willing to stand behind if your words were made public without your consent.