One of the most intriguing new features is the stock picking game, which was actually launched last March as MarketPerception. Users are awarded points based on the success of their picks, and data on the top 10 pickers, the most picked stocks, and the stocks with the most bullish and bearish predictions will be available to site visitors.

The social networking features of MarketWatch are basic, but solid. Befriending someone lets you keep track of their activity stream on the site -- picks, comments, recommendations (article ratings), all of which can also be subscribed to via RSS. It would be nice if CBS allowed users to communicate with each other more directly to do things like discuss investment strategies or debate the latest Wall Street news. Check out a standard MarketWatch profile here.

So far, the new community features are paying off in terms of upping user engagement with the site, according to MarketWatch. In early tests, 47% of users made a stock pick, while 21% commented on stories. A quick scan of the site this morning reveals that most top stories have at least a handful of comments. "In beta we've experienced increases in user loyalty, satisfaction and length of visits," said Jim Bernard, general manager of MarketWatch.

Adding social features is the en vogue thing to do at mainstream news properties this year. MarketWatch is the latest on a growing list of mainstream news web sites that have added features like commenting, rating, or friending in the past 8 months. It will be interesting to see if these sites can build a cohesive community around their content and increase readership and advertising dollars, which is of course the ultimate goal.