Since you're using jQuery, you might as well just use show() and hide() or remove().

Also chaining: https://gist.github.com/1631368

I think that looks and scans worse. I didn't count characters, but it also seems like more characters. I bet it performs worse too (not that performance matters in this case).

or even better, use toggle():

    jQuery("#mw-sopaOverlay, .noprint, #footer, #content").toggle();

And execute the first command just on $('div')