Certain commentators are 'literally' in a tizz about the fact that the OED slipped in what is often felt to be the erroneous use of the word literally as an additional definition to the word's original meaning (namely 'in a literal, exact, or actual sense; not figuratively') in 2011, without anyone noticing.
Many people 'literally' get hot under the collar if the word is used in any way other than to say something happened in the way described by the actual words used, but people have been using literally freely in their sentences to add emphasis for more than 200 years.The OED has this citation from 1796: "He is a fortunate man to be introduced to such a party of fine women at his arrival; it is literally to feed among the lilies."
The OED does not regard it as its job to act as a moral arbiter on the English language, nor to prescribe or proscribe any particular words. It includes meanings that are in common usage and, if it sees fit, adds certain riders. In the case of the frowned-upon definition of literally, the OED describes it as 'colloquial' and says 'Now one of the most common uses, although often considered irregular in standard English since it reverses the original sense of literally (‘not figuratively or metaphorically’).' The definition added in 2011 reads: "Used to indicate that some (freq. conventional) metaphorical or hyperbolical expression is to be taken in the strongest admissible sense: ‘virtually, as good as’; (also) ‘completely, utterly, absolutely’."