Here is research from an assistant professor of marketing at Penn State that is intriguing on many levels.  If you have a particular interest in corporate logos, this is a must-read.

One of the key ideas is that a brand’s most loyal customers tend to react most negatively to logo re-designs – and that those negative reactions can reduce the attraction they feel toward the brand.  Casual customers typically don’t care.

So that has implications for market research, according to the authors – when asking consumers about logo re-designs, don’t worry much about casual customers.  Focus on the brand zealots.  And give those hard-core consumers a sense of ownership over the re-design.