That's generally a bad idea. You'll find your members wanting to talk about things that you might not have even considered. Additionally, unless you yourself can post at least one good quality post in each forum every day, it will continue to look "empty", and that's a bad indication for any forum. If you have a look at any unsucessful forum on the web, and there are plenty, that is generally a common theme - loads of categories and no posts.
The best approach is to start with a fewer number of forums (the minimum) and start to split into new categories when it becomes obvious to do so (you'll know it when it happens).
That's the general rule of thumb and works well to ensure that the forum looks busy and active.
Split when you have at least 20-30 threads which you can move immediately to the new forum.
Divide and conquor is a good tactic.