EBiz MBA recently published a table of the top ranking social bookmarking sites. Right at the top is Twitter, which surprised me, because I don’t think of it as a social bookmarking tool at all. Twitter might be a good place to share links with others, but if you post a link and then 6 months later think, “Hmm! What was that really useful link I posted on Twitter about sharing data between online services?” you’re probably not going to find it. It might also be good for finding recent links that have been posted to the social network, but it doesn’t store them in a way that makes it easy to retrieve them again at a later date. ie months or even years. To me, the key function of social bookmarking is to be able to store and retrieve links wherever (anywhere I can access the internet) and whenever (years down the line). The ability to share those links and find other related links within the social bookmarking service is also useful, but only on top of the bookmarking functions.