In a posting Thursday on the Facebook blog, the company said that it's starting "a small experiment to test the usefulness of economic signals to determine relevance." The test, Facebook said, would give the small number of test participants the option of paying to have a message sent directly to the Inbox, instead of ending up in the Other folder, of a recipient with whom they are not connected.

The company said that "several commentators and researchers" have pointed out that "imposing a financial cost on the sender" would be the most effective method of discouraging unwanted messages -- or of facilitating the delivery of relevant and useful messages.

Two New Filters

A typical use case, according to Facebook, might be a Facebook user wanting to send a message to someone who gave a speech the user heard, but who is not in the user's online social circle. Similarly, Facebook said, a user might want to message "someone about a job opportunity." It's not clear if Facebook envisions someone looking for or offering a job, although it could be either.

Some Facebook-watchers are suggesting that, in addition to being another possible revenue stream for Facebook, it could be a way to limit spam. However, $1 per message might be an acceptable charge for mass mailings from a large corporation or political group.

This test would seem to run counter to Facebook's basic premise -- staying in touch with your chosen social circle. The new pay-for-Inbox-access opens the possibility of bombardment by job seekers or promotional campaigns. The company did say that, at least during the test, the message routing feature is only for personal messages between individuals in the U.S., and the maximum number of such messages that a user might see is one per week.

The company is also introducing two new message filters, outside of the $1/message test. The Basic filter limits your Inbox to messages from friends or "people you may know," such as friends of friends. Basic is the same as the previous settings of "friends of friends" or "everyone."

New Privacy Settings

The other option is Strict Filtering, limiting your Inbox only to messages from friends. In either case, less desirable messages go to the Other folder. This setting is equivalent to the previous Friends setting.

Meanwhile, Facebook is rolling out new privacy settings, beginning with users in New Zealand. This latest round includes a privacy shortcut menu that is now part of the main toolbar at the top of a user's page on Facebook, and controls are broken down by specific questions, such as "Who can look me up?"

The Facebook empire is still echoing from the noise this week over changes in terms and conditions at its Instagram site. On Monday, Instagram's new Privacy Policy and Terms of Service were published, and users revolted over language indicating that the site could incorporate users' names, likenesses or photos into ads, without payment to or permission from users. Instagram subsequently said this interpretation was "not true" and that it was working to clarify the language.

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