Great addition, but why not write it as a userscript instead of Chrome plugin? Chrome, Opera support them natively. You can install it just like an extension. Firefox needs Greasemonkey to be installed but most power users have it anyway.
Not sure about IE and Safari but problably they can support userscripts in some way also.
I wrote something like this as a user script that works in FF(w/Greasemonkey)/Chrome/Opera a while ago [1]. The idea is to remove individual stories or add filters rather than removing everything like the OP. My script is based on VI-style shortcut keys though so that may influence how useful you find it.