A few years back I was speaking about using social media in a crisis at a CIPR conference. During the course of that talk I coined one of my favourite mantras: "publish once broadcast widely" (I have quite a few). Interestingly I've heard this coming back at me a number of times since, which in many ways is quite gratifying. The difficult bit is some people have misinterpreted it.
So to clarify, in a crisis you have one landing page or site on which you publish all relevant and important updates. Then you use all channels available to you to link back to the landing page. You then set about actively discouraging anyone who takes the information and re-interprets it. You persuade them to link back to the original text on your landing page.
Common sense really but you'd be surprised!