When the “Wisdom of Crowds” turns on itself: IMDB Edition
The concept of the wisdom of crowds is a fundamental building block of a lot of the Web 2.0 services that we see today. While not all of them are built on this core concept, major sites like Digg, Wikipedia, and Mahalo rely heavily on crowds being wise. There have been several instances of this system breaking down in the past, one notable occurence being the infamous Digg HD-DVD revolt. On occasions like this, a mob mentality tends to take over a very vocal and active segment of a community, greatly skewing the product of their collective "wisdom." We are seeing the latest meltdown of crowd wisdom over at IMDB, the popular movie information database as we speak.

Since the release of The Dark Knight, the film has made an incredible surge to the number one position on IMDB's Top 250 list, a spot that has only been held by The Godfather for the last decade or so. While most serious movie watchers would argue that claiming that The Dark Knight is the best movie of all time is ridiculous, we might be able to chalk the massive surge up to the unparalleled amount of hype that surrounded this movie, particularly in internet communities.
Since The Dark Knight's initial rise, an even more interesting trend has revealed itself. /Film is reporting that, in an attempt to keep TDK on top, fans of the movie have been voting down The Godfather. The movie has gotten hammered so bad by Batman fans that it has fallen to the number three spot. So, not only has The Godfather dropped out of the number one spot for the first time in a decade, but now it has dropped from the second spot as well. This sort of drastic shift hardly seems the work of a wise crowd.

The Dark Knight has taken the top spot on IMDB, while The Godfather, the previous number one for the last ten years, dropped to number three.
We are seeing a similar effect here to what happened with the Digg HD-DVD debacle. This mob mentality, brought on by a significant event (in this case, the release of The Dark Knight), causes a total breakdown in a system that is otherwise fairly accurate, useful, and trustworthy. The original theory of the wisdom of crowds discusses this sort of failure. A quotation from Wikipedia on the topic reads, "...in these types of situations their cognition or cooperation failed because the members of the crowd were too conscious of the opinions of others and began to emulate each other and conform rather than think differently." Cases like what is happening on IMDB's Top 250 right now are not the fault of the users of the site. They are just acting how humans have always acted. Mob mentality is in our nature. We are always being influenced heavily by these outside sources. Sites like IMDB and Digg need to be setup in order to deal with and process the effects of an eventual mob action.
I am still a firm believer in the wisdom of crowds. I think that it is a tremendously powerful concept that can be applied to a variety of areas. However, if it is not implemented correctly, you will occasionally get breakdowns like we see here. In the cases of Digg and IMDB, these breakdowns happen infrequently enough that it is not a major concern and does not usually disrupt the use of the site. That said, we have seen, with some consistency, that the system can be broken or manipulated by the actions of a passionate group of individuals, acting as a mob. If these incidents are not largely prevented in the future and become commonplace, we risk a lot of people losing faith in this otherwise very useful system.