Just like the search filtering options, the input field of this widge too accepts plain text values for filtering the forums. Isn't really a good idea, because you have to remember the names of the forums/spaces that you have to filter. For example I use "JBoss AS" to filter out the JBoss AS space. Ideally, this should have been a selectable input which would list the available forums/spaces and users could just click on them.
Ah, IE actually shows some dropdown there. But you can still only filter on one area? Another strange thing is that when you default to "Community" you get recursion but when I tried picking "JBoss AS", I just got the top level.
In a perfect world, everone would use the "Question" feature and then people could choose the categories they'd like to help out in and just use that widget to filter for those unmarked questions. In that same world, every JIRA would be associated with a failing Arqullian test case again trunk but I should really wake up now :-)
The Unanswered Questions widget displays all the unanswered questions within a space as demonstrated in Website Issues. This too is restricted to a single space but you can add multiple widgets configured with different spaces on the Your View tab in your profile.