While both are accepted,..the short form is more normal during everyday useage. Most words used in English, whether written or spoken, will default to the shorter or slang version. ...in the case of re·cap it is used as a VERB state again as a summary; recapitulate: "a way of recapping the story so far" · "to recap, it’s been a year full of ups and downs" NOUN a summary of what has been said; a recapitulation: "a quick recap of the idea and its main advantages" Shorter versions are almost always the preference for spoken english sentence structures. "Keep it simple, short and sweet and your listeners will be at your feet!"