VentureBeat

Social bookmarking was one of those hot areas for a while back in 2006, as Del.icio.us and StumbleUpon exploded into popularity. Clones began to pop up everywhere, but few have managed to gain much ground.

That makes Diigo, a newer social bookmarker aimed toward information gathering that I reviewed last year, sound like something of a throwback. However, Diigo is releasing a new version today, and says it has a small but growing group of devotees.

Diigo is distinguished by its highlighting capabilities, which allow users to go through a page and mark certain portions. Users can also leave comments on pages, made visible by a Diigo plug-in available for most browsers.

That makes it great for research, but Diigo seems to be aiming at more of a mass audience with a set of new social networking and recommendation tools. Users can now join groups, send messages to each other and follow what friends are doing. Recommendations are provided based on your own bookmarking and existing tags and groups are available to search through, which can help new, friend-less users get started.

Diigo’s CEO, Wade Ren, told me that the service is getting some attention as a group research tool for people like teachers and marketers. It’s now somewhere north of 100,000 users.

Interestingly, Ren points out Delicious as the only competitor to his service that’s still innovating. However, it looks like traffic to Delicious is falling off, while StumbleUpon has spiked upward according to Alexa, Compete and Quantcast (click through for the charts). That may mean that the average user is actually interested in a less full-featured service.

Around the corner is Delicious 2.0 (coverage on that from TechCrunch), so we’ll soon have a chance to see.

Social bookmarking has been hot for more than a year, with webpage annotation — cutting and saving relevant parts of a website — a flourishing niche. Startups like Plum, Yoono and Grouptivity have all entered the space, and we reported in August that Clipmarks had been bought by Forbes.

One reason we’ve seen such a swarm of attention around social annotation is that the internet is a messy place. While search engines tackle the problem by pointing out the pages with the best content, social annotation harnesses the efforts of users to clip out and aggregate the best parts of webpages.

Diigo, which is opening its private alpha site during DEMOfall, is yet another iteration of annotation. More so than some of its competitors, the site attempts to build communities of users interested in specific subjects. The idea is to create social networks of engaged users, whether they are university researchers or fans of a TV show. By contrast, Clipmarks has few social aspects, only allowing users to pick out specific people whose content they enjoy.

The central feature, though, is still “clipping” webpages. For Diigo, this revolves around the notion of highlighting, just as a student might do to important passages in a textbook. After hightlighting a block of text, the user can comment on the importance of what they chose to point out.

Subsequent Diigo users visiting the same page will see the highlighting and comments. The content is also aggregated on the user’s profile, found through the main website.

On the Diigo website, the further dimension of community is offered. Users can gather themselves into subject-oriented groups, like stock investing or horseback riding, or instead join a group centered around a specific website, a concept Diigo calls SiteCommunities. For example, fans of obscure Wikipedia entries could start their community around that site, clipping out interesting tidbits.

Finally, the site also features a service called WebSlides, which allows users to mash the content they’ve discovered together into slide shows for others.

Diigo’s founders, Wade Ren and Maggie Tsai, are former investment managers who, like the lawyer who started Clipmarks, set out to make a tool helpful to themselves. Tsai notes that she doesn’t expect casual internet users to visit Diigo; rather, she thinks that anyone who reads extensively will find it useful.

Tsai also noted that the trend of annotation will move beyond any existing service, saying, “We’re the tip of the iceberg as to what can be done with this idea.”

Based in Reno, Nev., Diigo employees 10 people full-time, but has not yet taken any venture funding. When fully opened, the site will supported by targeted ads and some premium services.