New Design for Message Boards
As I mentioned the other night, the Salesforce community forums (including the Developer forums) have undergone a redesign.
While it's largely cosmetic -- a MUCH cleaner look, IMHO -- there is a new tagging feature that enables you to set a tag or tags on any forum post.
Additionally, there are a couple of tag widgets and a "My Subscriptions" widget on the main forum page.

