I kinda think Madonna is pushing her luck here. Just a little. As in: Hey, Madonna -- you are just one of the people that history will forever refer to as one of the horrible people in the story about the Aurora movie theater shooting. While obviously not nearly as horrible as the person who committed the crime, nor as horrible as the people who believe that the massacre would have been prevented if the people in the audience either had more guns/religion, or even more courage. (Really.) But as an American musical and pop culture icon with many fans, when you are told that after a mass shooting that injured almost 60 people and killed 12 that using fake firearms in your show for fun is a bad idea, you should get your head out of your ass and listen to them. No one cares if this has been part of your tour since before the incident took place. The incident happened, and you have to do something different for a little while (not forever!), so as to avoid looking like an insensitive dick.
I love the last line: "It's just so...tacky." Madonna! Tacky! The hell you say!
But before we attempt to calculate exactly how long the moratorium on fake guns in stage shows should extend in order to effectively communicate...something, allow me to say this: Madonna is a hollow entity (and why you're looking to her for reassurance and behavioral cues at a time like this is far beyond me). Her performances are meaningless events. Plastic guns are empty symbols that do not contribute to real violence, and renouncing their public use for an indeterminate length of time is an insultingly insignificant gesture that does nothing to reduce it. Either work to change the political reality surrounding guns in America, or grieve quietly and move on, but insisting that everyone else enter your hall of mirrors is useless and annoying. Your tantrum, while undoubtedly heartfelt, is only slightly less unnecessary than a compilation of celebrity reactions to the shooting, the audio clips of the 911 calls, and other self-serving pageview bait. Consider this: maybe what you should really be offended by is the ease with which you can apparently be placated by superficial pantomime.
Now, if you'll excuse me, I'm going to go organize a moment of silence on Twitter.