[tubedogg]

That brings up an interesting point, Chris - how to handle having a very large number of forums. Here's my thoughts on it - two different ideas:
1) Do it similar to how the templates are currently listed in the Admin CP - in groups that can be expanded one by one. You set your prefs group by group, hitting submit each time. Although now that I think about it this wouldn't work too well.
2) Page one is a list of categories. Click on a category, you get a list of forums in that category. Check off the forums you want, hit submit, you get taken back to the list of categories. Sub-categories (and subsequent sub-forums) could be handled one of two ways:

• List them, indented (with sub-sub-categories being indented twice as far, etc.) on the main category list page, or
• List them on the appropriate forum selection page (e.g. category "a" has a subcategory "b", so list it when you click on category "a", but don't list it when you click on category "c"), in a separate box (so it's clear what they are) and clicking on one submits your choices of forums *and* takes you to a list of forums in that subcategory. Sub-subcategories would then be listed on this page, and so on.

Personally, I like the second idea better, and I like the second way of listing sub-categories better.

Just some food for thought.