Amazon figured out social shopping and e-comm - social e-commerce - a long time ago. They made it easy for consumers (aka prosumers) to make recommendations, write reviews and then share the information with other users. Although, I am not surprised that these ideas failed to catch on with most businesses. Interestingly, most businesses today are missing out on web 2.0 too.
You know, the static ones with old information. Or one where you couldn't find the information you wanted? The kind where the customers needs were an after thought. I dread those. You see them all over the web. From small business sites to medium ones and even large company sites. They all suck.
Open source, like the blogosphere, is a grassroots (bottom up) movement. Try not to let the grassroots lull you into believing that it is about one or two people with an idea or cause. Today's grassroots ideas on the net become viral in days, scaling in volunteers (Seth, will you help us) to what would make any organization or marketeer cry for mercy or celebrate in the streets. But, that's not happening in most business organizations. Too bad.