Usually we try to write a FOW every week but the last one is three weeks old. We are currently very busy since there are several things going on. Besides the ongoing work to improve BibSonomy (fixing bugs and implementing new features) we are also actively working on new research results. Further, the deadline for this year's ECML PKDD Discovery Challenge is approaching and we need to prepare some things for that. E.g., we were able to get very nice prices. The challenge is still runing... But this are only side remarks.

Back to this week's FOW: With the March 2009 release we introduced a new group feature called "relevant for", with which group members can particularly flag posts. Why do we need this new group feature? The implementation of our group system follows two main ideas. On the one hand, it is designed to provide access rights, which means that users can restrict the access of a post to the members of a certain group (only group members can then see this post). On the other hand, it is a system to collect posts of group members which allows for aggregation. Due to a lot of support requests we realized that this kind of combination is not very
intuitive. So we searched for a way to maintain both parts but separate them and make the whole system easier to use. The "relevant for" feature is our solution to overcome this problem. The corresponding page is intended to support groups -- especially research groups -- by collecting bookmarks and publication with a special topic. As it is possible to choose more than one group a post is relevant for, posts can be dedicated to more than one group.

Let me explain how it works. The way we implemented this feature is as a system tag. What does this mean? On the bottom right hand side of the posting dialog you find a form called "relevant for" which contains a list of all of your groups. You can choose one or more group you think the post is relevant for. If done so, the post is annotated with special tags "sys:relevantfor:groupname" for each group and these tags are stored as usual tags and can also be changed by the user. We are working on a mechanism to hide these system tags from the usual website and tag clouds but currently this feature is not yet finished. To make the system tag useful, we implemented a special page "/relevantfor/group/groupname" which shows a collection of all posts tagged with the corresponding system tag for this group. This feature is
independent from the access rights of groups. As long as the user has the rights to see the post he will see the post on the corresponding pages.

To summarize it: groups are no longer only for access rights but also topical groups and if someone is interested to open such a group, we suggest to just register an account, send us a an email, and we will turn the account into a group and you can work with it.