Since this is all automated it wouldn't require any more human intervention than present... I would separate the RSS feeds out by sub-category as it is now so it's not so overwhelming when trying to look through the lists. The nice thing about this is that the server doesn't run up the bandwidth sending emails to everyone subscribed every time a new post comes in. But even if you're browser is up and actively looking, it's only subject text coming in, not the entire context of an email. It ain't much, but it all adds up. Might also help the mods scan for questionable post subjects.
Please add my vote for feeds, rss, atom, etc. Great and obvious idea. Much easier for people to keep up forums who have only occasional or time limited net access. good feed readers can limit how many messages to download or just download the subject/header info. even if you had a million messages a day, most readers can be set to d/l 100, 500 posts or whatever. with a feed reader I can connect to the net and in less than 5 minutes can download 5000 posts that I can read offline. this would obviously benefit a lot of rvers that only have occasional, temporary net access. I would recommend setting up feeds for active posts, new and popular. then if it works ok, set them up for new posts on the individual subject forums. once people learn how to use this feature, not too hard really, I think you will have a lot of happy customers. most of the newer, updated forum software is starting to include built in capability for generating feeds, so it's getting pretty easy to set up.