Went through and deleted a large number of categories expecting the posts to move into the category specified as the Default Category in Settings > Writing.
However, the posts now all show "uncategorized." Not that they are in the category "uncategorized," but that they literally have no category associated with them. No category is checked in the edit screen and it shows an un-hyperlinked "uncategorized" in the post list.
Without the category association, there's doesn't seem to be any way to even run an SQL query to move them into another category. It's like they are just hanging out in some taxonomical no-man's land.
Help? Thoughts?