Just some feedback for future updates to the WP plugin: some WP blogs have multiple sidebars... for instance, one for the index/home page, another for posts and pages, and yet another for archives and search.
Currently, the Vanilla sidebar widgets allow for only one instance of themselves. So if you run a professional blog with different sidebars, you can only have one Vanilla Recent Discussions widget on only one sidebar throughout your WP installation.
Would be best if the widgets were unlimited in their amount of use, allowing them to be used across a single sidebar of 10 sidebars. This is the case with the WP "Text" widget as well as other WP sidebar widgets.