As a company that specializes in Online Reputation Management our monitoring tools are now showing Twitter as the dominant place to watch for your brand name. It is intersting to see how a random thought input by a bored tweeter can appear so negative. Keep your brand monitored at all times. The monitoring tool we use is called Trackur developed and distributed by one of the pioneers of Online Reputation Management Andy Beal. There are other much more expensive tools out there but Trackur does the job for us at a great price.
Here is another list of crisis management tools I found by Jonathon Bernstein Crisis Management Monitoring.