I have a problem. I stumble. And it has nothing to do with my legs. I am addicted to StumbleUpon. I take childish delight in finding new and unexpected Internet treasures every time I hit that tantalizing button, beckoning with its flowing blue and green “SU.”

For those of you who live deprived as I once did, StumbleUpon is a social search engine. It plugs directly into Firefox or IE7 as an integrated toolbar. Your search is random but limited to areas of interest you select. In addition, possible results are also filtered based on the ratings of other users. You only see what collaborative opinion has deemed worthwhile. You can also integrate any site into the network by giving it a simple thumb up or thumb down.

Watch out, Google, I think we are looking at the method, if not tool, of future Web browsing. Sure, you will use Google or Yahoo! if you need an address, thesaurus, or other clearly defined reference tool. However, if you want to find interesting and entertaining sights, you will Stumble. You will have a higher probability of quality content based on consensus than by searching by subject or keywords. I have come across more useful and entertaining sites in a week with this tool than in years of Googling. And as more people join, it should get even better based on the refined ratings.

With my work hat on, I also wonder what the implications for Web marketing and advertising will be. Paying to place your links in searches isn’t an option. And if users give you enough thumbs down, you are out of the game. Will this really bring the quality of content to the forefront, or are there more sophisticated ways to push users so that they stumble in the right direction?