Every year, the American Dialect Society nominates and then votes on a word of the year, and for 2012 it's "hashtag." It beat out other nominated words like "YOLO," "Fiscal cliff," and "Gangnam style." The ADS' chair of the New Words Committee, Ben Zimmer, said that the word was a "ubiquitous phenomenon in online talk" in 2012. He's not wrong, the term broke out from its origins on Twitter to more common usage, culminating in Newsweek's last ever print cover. Zimmer added that "hashtag could sometimes be heard in oral use introducing a snappy metacommentary on what had just been said."
The ADS promotes its word of the year over others by dint of its academic members and lack of commercial interests. In years past, "Occupy," "App," and "Plutoed" have all taken the honor — so there's no promise that "Hashtag" will have real staying power. If nothing else, the award for the word "Hashtag" could offer some future consolation to the baby that was reportedly named "Hashtag."