In June 2013, Facebook announced the introduction of functional hashtags to the network.  Currently, they are available to a small audience but will "roll them out more broadly in the coming weeks."

They offered these four tips to for marketers:
•    If you are already using hashtags in an advertising campaign through other channels, you can amplify these campaigns by including your hashtags in Facebook advertising. The same creative best practices on Facebook still apply – compelling copy and photography that is in the brand voice works best.
•    Any hashtags that you use on other platforms that are connected to your Facebook Page will be automatically clickable and searchable on Facebook.
•    Like other Facebook marketing tools, hashtags allow you to join and drive the conversations happening about your business. We recommend you search for and view real-time public conversations and test strategies to drive those conversations using hashtags.
•    Hashtags do not impact your distribution or engagement in News Feed on either desktop or mobile. We recommend you continue to focus on your existing campaigns to drive your most important business objectives.

It is to be seen whether or not this will be a helpful tool or just more noise in the social strata.