Propeller was the first social bookmarking site I used. Along with other sites like Digg. For me, i like a social bookmarking site that has ability to vote up/down a news story or link. Also, a site that allows comments. Here's a very good list of the most popular social bookmarking sites (along with a few social networking sites that have bookmarking features). http://www.moneytized.com/top-social-bookmarking-sites-list Please take a look and see which ones are your favorites. Discuss why those bookmarking sites work for you.