Oooh, I really hope the sidebar blocks can be customized per forum (or category, in other parts of the site). This would be a perfect way to link content from various parts of my site. For example, in my forum for discussing upcoming conferences, I could have a feed block from my custom conferences database showing the upcoming conferences, or a block with links to external websites for those conferences. Likewise, in my conferences database, I could have a feed block showing all recent forum topics from my conference discussions forum.