It's not like you get to pull a name out of thin air and message it for a dollar, it tells you things about people you can't normally reach (IE normally have you blocked from sending messages), and lets you decide if you want to reach them anyway, despite the fact that you are normally blocked/put into other.
The wonderful spin they put on this is: "For the receiver, this test allows them to hear from people who have an important message to send them."
That important message could be "i'm stalking you, bitch", being sent from a throwaway facebook account. As the article points out it also allows you to send messages to people you aren't friends with, so you don't even have to have gotten them to friend you. Normally it would have gone into other and you'd likely never have looked.
[1] Though i think you can probably see this it the next step if this test is "successful". Recommending to advertisers that they spend X dollars to get into the inbox of X people who share Y interest.
But you are dismissing a perfectly legitimate use. I had no idea there even existed an "Other" folder and when I did find out, there were a half dozen legitimate mails from longlost friends of various types.
I can see the privacy concern here but to call the above "spin" is being ignorant to a very legitimate use case. The $1/msg seems like an interesting compromise - if someone legitimate really wanted to reach me, they probably wouldn't mind spending a dollar.
If i have a setting that says "i only want to hear from friends", then i only want to hear from friends. That's the choice I am making about who i want to hear from. You can argue i'm not thinking this choice through, or am ignorant of the consequences, but that's not the same argument.
If they want a setting for "I also want to hear from people who are willing to spend money to reach me" (or some better pr worded version of this), great, i'm not opposed to that.
The entire point of this exercise is to address zaidf's use case, which is trying to attach importance to messages that are outside the realm of Facebook's "important" data points. If they aren't your friend, and they aren't a friend of your friends', but they still have an important message -- how can we identify this?
The obvious hope here is that they can identify important messages by attaching a small (but real) cost to them, while limiting abuse by way of rates and maybe tweaking the cost.
You may not want these messages, but the fact remains that there are important messages that go missed because they can't smartly be deemed "important" in the Facebook ecosystem. Maybe there are sinister intentions beneath the surface, but this is still a legitimate attempt to solve a legitimate problem.
I am sure that even when they roll out this feature, they will give you an option to turn it off just as users right now can remove the Message Me button from non-friends entirely.
You seem to assume that facebook can or should be the way to reach people who have explicitly said "friends only" for their facebook messages.
Again, if i've said "i only want to see messages from friends", and something "important" goes missed as a result, that is the tradeoff I chose. The rest of this argument seems to be "you chose the wrong tradeoff or we think you don't really understand what you are doing so we are doing our best to surface stuff that you explicitly said you didn't care about"