There is a lot of talk about the Facebook email test which was unveiled the end of December 2012. The experiment is aimed at generating new revenue for the popular social networking group by assessing a $1 fee to send a message to non-Facebook friends.
For now, the Facebook email test is limited to individuals. Brands, companies, and fan pages are exempt, but likely to be included if the experiment proves successful. Individuals who are included in the test have the option to pay the $1 fee to ensure their message is delivered. Otherwise, the message sent to unconnected friends will likely end up in the "Other" folder.
Few people are aware of the "Other" email folder, let alone how it's used. Its primary purpose is to store messages that have been filtered based on personal preferences. Facebook provides two email filtering preferences which include basic or strict. Any messages that don't meet preferences are automatically sent to the "Other" folder.