Originally Posted by
Midlifecrisis 
Sorry, off topic. But it there some truth the the rumour that private messages will be able
To be seen one day by all?
That was a slip that actually happened. Last year FB released a new format to their profile pages, called "timeline". As part of it, old private messages from years ago showed up publicly. (I think from 2008 prior). It was an accident but they didn't fix it as far as I know. I can still go back on my own timeline and see messages that were clearly private. (Thank goodness all of them consist of very boring "let's hang out next time I'm home" type messages).
So, while they don't have plans to do that again, I think that incident was a good indication of how they treat data. They have pretty consistently shown that they will constantly push things to be more public, so I treat even private messages as potentially public.