Amazon.com has long been a leader in customer participation among retail web sites. If you haven't been to Amazon in a while, take a quick look at the page for Freakonomics to get a feel for what Amazon is doing now.

Product pages include tons of user contributed information, including:

Customer Reviews
Customer Ratings
Ratings of Customer reviews
Customers who bought this also bought ______
Customers who views this also viewed ______
Listmania (customer generated lists of items that include this item)

And now they have new features, including tagging:

Customers tagged this item with ______
Customers who tagged this item are ______

And now the ProductWiki ( Customer-editable product information).

What the heck is a product Wiki?

Wikis are collections of information that are editable by all. For example, maybe you know something about the book Freakonomics that isn't already mentioned on Amazon. Now you can share that knowledge with all future visitors to that page of Amazon's site with a couple clicks. The wiki evolves over time as people add their two cents, ideally improving the content.

Why is Amazon getting into Wikis?

Amazon is in the business of selling products. A lot of products. Their expertise is in managing inventories and making good use of customer data. They do not know, or pretend to know, anything about the individual products they carry on their web site. That expertise comes from a combination of customer behavior (people who bought this also bought ___) and user contributed data in the form of reviews, ratings, and now Wikis.

How does Amazon benefit from this?

Anything that increases the odds of an Amazon customer having a good buying experience is a good thing. What are the odds that you'll find a given book you buy on Amazon memorable? Those odds go up as Amazon provides more guidance through aggregated consumer behavior, and now wikis. Descriptive product content coming from genuine experts (people who've read the books, used the kitchen gadgets, bought the plasma TV) increases consumer confidence, increases the odds that Amazon will have a satisfied customer, thus increases Amazon.com's bottom line.

What do you think? Will Amazon's ProductWiki catch on? Do you think the success of Amazon's wiki will correlate with future sales? Does Amazon already provide enough information for consumers without a Wiki?