The same used to be the case for companies who had 'bad news days'. They would sit out the bad news and spring back when the public had forgotten (or something more important had taken the focus).... Well, that was until social media made a playground out of bad news and online activists were given the tools to constantly wear away at the walls of a company's reputation.
“With consumers increasingly using social media to share feedback on their
care experiences, it has become increasingly difficult for businesses to ignore
or hide from bad experiences,”
Lynda Kate Smith, vice president, Care Business, Nuance Enterprise Division
However, this activity gets worse when this activism goes viral. Then, rather than this being a constant 'negative buzz', your company is subjected to a barrage of barracking.
This recent posting on the Social Media Influence blog by Bernhard Warner of Custom Communications shows the history and impact of a company (he doesn't name for obvious reasons): http://www.socialmediainfluence.com/2008/05/case-study-the.html