The Harvard Business Review or other business school magazine will be covering the 2010 crises for lessons learned, and someone will try to make money writing a book about these crises and how the companies should have avoided making them worse.
It's always easy with hindsight. That said, gathering lessons learned can help developing and executing your crisis plan. (Check out some lessons learned here: PR Lessons from BP, Toyota & Goldman Sachs.)
Without a plan -- and sometimes, even when you do have a plan -- a crisis can alter the perception of the organization, cloud their minds when it comes to objectively assessing the facts, the internal and external perceptions, the priorities, even the right move. Having a plan helps identify the priorities and action steps.
Of course, having a plan does not prevent the distortion, does not prevent the exhaustion that can cause more problems.
One thing that can get overlooked during a crisis is the need to communicate to your employees, customers, and partners.
For public companies, it's critical to communicate with your board of directors and major investors. Even if you handle the situation, you may lose the confidence of the board or shareholders if they feel you have not been honest with them. That's part of the reason H-P's board pushed out Mark Hurd, despite the fact he had turned around the company. Poor communications with his board after a poor response during an ice storm is part of the reason that JetBlue fired its founder David Neeleman. Good communications plans identify in advance who the crisis team needs to keep informed.