Marvel - stealing language?

Indispensable web resource Boing Boing carries an article lambasting Marvel (and to a certain extent DC) for attempting to appropriate the word 'super-hero', with both companies attempting to file a trademark on the word. I can see why Marvel or DC would stampt (TM) and (C) over their creations such as the Superman shield or Spider-Man emblem, but, as Boing Boing points out the word super-hero is a word which is in general useage and has been for a long time - plus if the big two successfully claim the ownership of the word does this mean that every independent comcis publisher will no longer be able to describe their characters as super-heroes? Will we need to pay a royalty every time we use the word on a blog or magazine article? I'm left with the distinct impression that a super-villian (TM) may be behind this whole thing as an attempt to remove many super-heroes (TM) from circulation - what a dastardly plot (C).