Oh, Cap', I certainly didn't mean to imply that the majority of the English-speaking world uses the phrase to pick up a room to mean to tidy up a room. I simply meant that the majority of the English-speaking world could figure the term out easily in context, yet those who were not fluent in English would have difficulty with it.

To my American ear, tidy up, which I've read, of course, sounds feminine. I would never imagine a man speaking of 'tidying up' a room--just as, I suppose, you cannot imagine a woman such as I picking up a room. ...or anyone else, for that matter, I suppose!