For a company that’s all about helping people wander the Web and make serendipitous discoveries, San Francisco-based StumbleUpon has been on a remarkably straight path since 2002.
That’s not to say the venture-backed company hasn’t gone through big changes. It has: from tiny Firefox add-on maker in Calgary, Alberta, to angel-funded SoMa startup, to eBay subsidiary, and finally (in 2009) back to being independent.
But throughout those changes, StumbleUpon’s technology and business model have stayed remarkably simple and consistent. Turn on the company’s browser extension or Web bar, and you’ll see a “Stumble!” button that will take you to a semi-random website or video chosen to match your interests. You have the opportunity to give each site a thumbs-up or a thumbs-down, share it with others, or write a review—information that helps StumbleUpon’s collaborative filtering algorithms improve future recommendations for you and people with interests similar to yours. Every 20th stumble will take you to a sponsored site; publishers pay StumbleUpon 5 cents per visitor.
That’s it—that’s StumbleUpon’s whole business, and always has been. Of course, the company has introduced variations such as StumbleThru—a way to discover content within specific sites like PBS.org or Wikipedia—and it’s got nifty iPhone, iPad, and Android apps for stumbling on the go. But the only dramatic change at StumbleUpon, apart from its short-lived fling with eBay, has been the growth of its audience.
Today the service has 12.3 million active users who stumble about 600 million times per month. As a source of social-media traffic to sites around the Web, StumbleUpon is second only to Facebook—it accounted for 33.4 percent of all visits from social-media sites in October, compared to Facebook’s 43.8 percent, according to statistics from Web analytics firm StatCounter. StumbleUpon far outranks Twitter and social bookmarking sites like Digg, Reddit, Delicious, Slashdot, or Y Combinator Hacker News. Yet for all that power, StumbleUpon is rarely mentioned in the same stories with media darlings like Facebook—which has led ReadWriteWeb’s Richard MacManus to call the startup “the silent social media success story.”
Part of the reason for the company’s relatively low media profile may be that few journalists (at least among the ones I know) have time for undirected skimming. StumbleUpon is definitely not the tool to use if you’re in goal-directed research mode—you stumble when you’re in the mood for something new or unexpected. “It’s not a replacement for search engines,” says StumbleUpon co-founder and CEO Garrett Camp. “It’s for when you want to explore and see what’s out there.”
True, you could always turn to Google or other search engines for this purpose. If you’re daydreaming about where to go on your next vacation, for example, you could try a vague search query like “cool places to go.” But if you do that, Camp argues, there’s roughly a one-third chance that the sites you find will be blogspam, whereas every site in StumbleUpon’s database is either filtered by other users or sponsored. (Even sponsors’ sites get filtered out if enough users give them a thumbs-down.)
You can also lean on Facebook friends as a kind of proxy discovery engine, and many people do, as StatCounter’s statistics show. But link sharing isn’t what social networks were really designed for, Camp argues. “On Facebook, people share stuff and
