StumbleUpon gets into Google (and Wikipedia and Yahoo and Flickr...)

StumbleUpon, a fun Web discovery service, is getting a new feature, SearchReviews, that will take it beyond its historic role of hyperefficient time-waster. It could make it an integral part of the day-to-day browsing experience. SearchReviews pushes StumbleUpon ratings and other information into the search results pages on major search engines and content sites like Wikipedia, Google Reader, Flickr, and YouTube.

Users who run the StumbleUpon toolbar will now see little icons after search results on these sites that show them how popular a site is in the StumbleUpon community, the number of thumbs-up ratings it has, and who of their friends has rated the page.

It changes the way you look at search results pages. Now, instead of just looking at a sea of links in descending order based on what your search site thinks is most important, you also do a quick visual scan of the results for little StumbleUpon icons that indicate that actual humans have marked the page as worthwhile. If you happen across a site that a friend has flagged, you'll have an even better indication that the site is something that you'll want to check out.

If a page comes up in a results page that you've already flagged, you'll also see that rating (thumbs-up or -down) in the list of icons, reminding you of your own opinion of the page.

This is better than the social search that Hakia offers, for a few reasons. Most importantly, it doesn't require you to change your search engine. The new StumbleUpon icons show up on the search pages and sites you're already used to. And like Hakia, StumbleUpon will link you to discussion pages, but unlike Hakia, you get other social data such as the list of users who liked the page, so you can see what else they also liked.

This new feature makes the StumbleUpon social network much more valuable, so StumbleUpon is also making it easier to add friends from your other networks to it: You can import your friend lists from popular online e-mail services, as well as from Facebook. The service is also getting an Outlook contacts importer as part of this update.

Ironically, while SearchReviews is being integrated in 11 high-traffic sites, it's not going to show up on its parent site, eBay. I got two reasons for this from Garrett Camp, StumbleUpon's chief architect. First, he said, eBay items are "temporal," and StumbleUpon is more about bookmarking long-lived Web pages. Second, the 18-person StumbleUpon team couldn't handle customer support for eBay's giant user base if eBay were to actively promote the service.

For future releases, the team is looking at a completely general version of SearchReviews that could evaluate (and display ratings for) every Web link on a page.

StumbleUpon makes money by selling sponsored Stumbles. The new SearchReviews feature completely bypasses the ad engine of StumbleUpon, so it won't be a direct revenue generator. However, since it makes the entire service more valuable, it could drive more users to adopt StumbleUpon, and encourage current registered users to use it more. Personally, I uninstalled the StumbleUpon toolbar months ago, but I'm turning it back on so I can use this new feature.

See also: Mahalo Follow and Streakr (review).