Wow, that's fascinating. If anyone has any more info on this, I'd really like to learn more.
http://www.cennydd.co.uk/2008/can-we-avoid-redesign-backlash...
"In a nutshell, a meaningless background was removed from a seller page. Pandemonium. After strong resistance the background was reinstated, to everyone’s satisfaction. In fact, the rebellious users were so placated that they failed to notice the designers slowly adjusting the background’s hex values over the next few months. The background got lighter and lighter until one day—pop!—it was gone."
Look under the title "eBay.com: Satisfying their Users with Gradual Evolution"