Auto reply stuff is gonna happen. Unfortunately, I am not sure you can set a forum to allow both topic and forum level subscriptions, but I will double check.
While we are here can I get some feedback on my 'friendlier'
subscriptions page?
I haven't linked it in yet to the 'My Subscriptions' link in the top right - that is there for comparison.
Note the new version only shows subscriptions for topics - the forum/category/borad subscriptions will be added later.
It also is sorted by last posted date, and has a link to the last post, and the date/time and author for the last post.
If you make suggestions for it I can improve it further...