nexialys: I haven't yet created an page for this Mod in the phpBB Admin Panel but trust me, it's on my To Do list
In the mean time however you can set which catagory that users forums are created in by opening
addforum.php and editing to SQL on line 151. In the SQL ($sql), it will have cat_id=1, change that to the ID of the catagory you wish to forums to go to. You can find that by moving your mouse over the catagory link on the phpBB index page and it will have something like index.php?c=x. x is the catagory ID.
RMS: That is actually a great idea but I have no idea how I would do something like that

I will have a look but if something like that is added, unfortunately, it will be a fair way away
EVERYONE: I have added a feature so that the user creating the forums can choose permissions for it. I have limited the options to ALL, REG and MOD.
Here is a screenshot because it looks crappy under the theme on my forums.
