Written by Alex Iskold and edited by Richard MacManus.
The social bookmarking market is in a steady state with two dominant players - del.icio.us and StumbleUpon. The rest of the pack, including Yahoo MyWeb, appears to be substantially behind. Can they catch up? In this post we attempt to answer that question.
We also take a look at how social bookmarking has evolved since del.icio.us. (even del.icio.us itself has evolved a lot!). We compare the features and approaches of the different companies, to see which has gained popularity and what has become the norm in this space.
The current social web era started with del.icio.us and the advent of social bookmarking. The simple concept of a tag has turned our interactions with the web upside down. The idea of being able to store your bookmarks online, share them with everyone and see what others have bookmarked - triggered the sequence of events that resulted in today's rich and social web ecosystem.
We used the e-consultant and go2web20 lists of social bookmarking services to select the companies. Note that we did not include any company with an Alexa rank of less than 100,000. We also did not profile social news sites (like digg) or social shopping sites (like Kaboodle), as they will be profiled in separate R/WW posts.
Companies typically do not reveal the number of users and activity, but we can do educated estimates. In a recent post on TechCrunch, Michael Arrington stated that there are about 53 million posts on del.icio.us. Based on the statistics mentioned at the time of the del.icio.us acquisition (by Yahoo) in December 2005, and the growth since then, we estimate the current number of people using del.icio.us at 500,000. From this we conclude that the average user on del.icio.us did a little over 100 posts. This is a pretty impressive number, although it might be the case that there is a fat tail and a handful of users with a huge number of posts.
If we use 100 posts per user as a guide then, we can do similar estimates for other social bookmarking companies. For example, since Blogmarks has a total of 514,205 posts, we estimate that they have roughly 5,000 users.
Here is another interesting angle... a search on Yahoo MyWeb for items tagged "food" results in 7,200 bookmarks. A similar search on BlinkList brings up 120 pages with 20 items per page - or 2.400 bookmarks. In other words, the number of posts tagged with a particular word or term can be used as another relative measure of the number of users.
Finally, here is another method for estimating the number of users. We took a recently popular web2.0 list url: go2web20.net, as well as all time favorite CNN.com, and looked at how many people have bookmarked these on various services. If we do this for a hundred or so randomly choosen URLs, we would get more precise estimates - but this is just to give us an approximation of the number of users. Here is a table showing our results:
The social bookmarking market is dominated by del.icio.us and StumbleUpon. These leaders split the market, as they bring orthogonal approaches to bookmarking - del.icio.us builds a hierarchy for people to browse (it does related relationships, etc.), while StumbleUpon is more of a random discovery system.
Meanwhile the other players in this market have a lot of ground to make up on the two leaders, based on our analysis in this post.