Having tested it, I think a quick search with 'search this forum only' ticked does not include sub forums.
Can someone confirm please?
I had someone search in a category with this option ticked and, of course, it returned no results. Which from a UI point of view is going to be confusing.
Thanks Brogan. Then it makes no sense to have that option ticked by default if you're in a category (which can only be the case if you have the admin option Node & Forum List -> Create Pages for Categories ticked)?