StumbleUpon Facebook app screenshot

Web content discovery service StumbleUpon is rolling out a new Facebook Timeline app today that allow you to share all the cool stuff you find during the day with friends and family.

StumbleUpon’s service lets people discover and share new web content based on a broad spectrum of categories. Users click a “stumble” button to discover new content, and then have the option of voting and commenting on the selection. As of October 2011, the service has 20 million active users, and over 1 billion “stumbles” per month.

“What we’re doing with the new app is marrying the best parts of both services, StumbleUpon’s content discovery with Facebook’s socialization,” said StumbleUpon VP of Business Development and Marketing Marc Leibowitz in an interview with VentureBeat. He added that the new app was a logical move for the company because so many of its own users are also constantly on Facebook.

Every time you either discover or give a “thumbs up” (a.k.a. like) to something, the new app will push that activity to your Facebook Timeline as well as the real-time news ticker feed. Adding a new channel, category, or StumbleUpon user also generates a notification within the Timeline. All your likes will get grouped together by category (as shown in the image above), which is probably more effective than the standard list of Facebook “likes” for showing people what you’re into.

Leibowitz said the company plans to add more functionality to the Facebook app as it makes sense based on user behavior, but for now there’s plenty to gain from just integrating activity updates. He pointed out that a person is likely to feel gratification for being the first among their social circle to share the funniest/weirdest/craziest thing from the web — which is something I agree with. The combination of StumbleUpon and the Facebook Timeline app has the potential to make your friends think of you as the foremost connoisseur of web content and curation.

And curating all the best links will naturally spark discussion. StumbleUpon has its own method for commenting on a discovered web page, but its far from the robust conversations that take place through Facebook.

“Each activity update for discoveries, likes, or favorites becomes its own social object that invites people to start talking about it,” Leibowitz told me.

The new Timeline app is specifically designed for current StumbleUpon users, but that doesn’t mean others won’t enjoy it vicariously through friends. And considering how good the service is at finding entertaining/interesting content, its bound to drive new people to sign up for StumbleUpon accounts and boost traffic. It’s also worth noting that community link sharing site Digg, which has content discovery elements similar to StumbleUpon, saw a huge boost in signups and traffic activity after launching its own Facebook app in February.

StumbleUpon’s new Timeline app is available today. However, to enable the app itself, you have to grant the service permission to link with your Facebook account through the StumbleUpon settings page.