Google's latest toolbar technology--Sidewiki--allows Internet users to "contribute helpful information to any webpage." That's right, any webpage. Even sites without comment, rating or review features are fair game with Sidewiki. It has been most accurately described as Internet "graffiti."

What does this mean for you?

If Sidewiki is used the way it is presented in Google's examples as a place for experts to contribute valuable extra information to a page, then it'll be great for users and site owners alike. But since we all know the Internet is not a happy magical land of unicorns and rainbows, odds are that Sidewiki will become an outlet for users to gripe, complain and criticize in ways they couldn't before--on the site itself.

To be clear, the content contributed via Sidewiki won't technically be on the page. Instead it will appear in a collapsable sidebar to the left as seen below.

Since online buying habits are heavily dictated by user reviews and comments, I predict that site owners will have to start paying special attention to their Sidewiki reviews to avoid negative publicity.

Sidewiki is currently only available for Internet Explorer and Firefox but a Google Chrome version is in the works.

What do you think about Google Sidewiki? Is it a valuable new tool or a threat to website owners who prefer not to include user reviews and comments on their pages?