Install it and fill out which areas you are interested in such as art, music and animals. You then you get a little toolbar with a 'stumble' button where other stumble users then recommend you websites. If you like the websites they are saved in your favorites.
Implications - The Internet is a huge place and it's nice to have people sharing the interesting sites they find with you. You may even find the site of your dreams. You can also rate certain sites so that other people will eventually come across them if they're great.