The Wall Street Journal, citing unnamed sources, reports this morning that Google is set to launch a dedicated module in Gmail that will let people share and view status updates from friends -- turning the free email service into a more direct rival to Twitter, Facebook and other social networking services.

As the WSJ notes, Gmail users can already alert contacts to their status in the program's built instant-messaging module. The new feature, expected as early as this week, would be more similar to the dedicated stream of updates and messages provided by existing social networking services.

Sometimes new features can be overblown as a competitive threat, but the potential for the search giant to rival Twitter and Facebook is generating lots of attention already. "HUGE!" declares internet entrepreneur Jason Calacanis. Clearly Google is one company with the potential to buck the trend we identified in this story: Twitter, Facebook, LinkedIn get free pass from potential rivals.

The Wall Street Journal mentions possible integration of alerts from Google's YouTube and Picasa into the Gmail social-networking stream. One additional point is that users of the company's Google Reader service can already follow each another and share links and messages related to the stories they're reading.

When you start to think about Google's far-flung online ventures in that way, it makes sense that the company would attempt to stitch them together more tightly through something akin to a social networking stream.

Google's move could also have implications for Microsoft, which previously announced plans to let social networks integrate their streams into its Outlook email program, through a special module.