Originally Posted by cherokeesam
Maybe not a cameo per se, but if you removed BW from IM2, you'd still have the exact same movie. Same as removing Hawkeye from Thor would do exactly nothing to change the story. Thus the complaints about these "guest Avengers" contributing exactly nothing to IM2 and Thor.
Without Black Widow, who'd find Vanko's location and reboot Rhodey's system?