If you sell products, you really need to watch anything that might pop up on the web - you can't counter everything, but you can try to get out in front of sudden memes. Take trans-fatty acids, for instance:

The Ban Trans Fats suit was eventually dropped, but BuzzMetrics' study showed that the damage had been done: Kraft and Oreo were mentioned in 17 percent and 26 percent of the 2.6 million comments about trans fats, respectively, showing that the public clearly linked the dangers of consuming processed oils with the company and one of its most famous products.

When your firm/product starts getting mentions like that - especially in a negative context - you really, really need to know about it. If your marketing team isn't looking for corporate mentions and likely keywords, you need to beat them with a cluestick.