There are RSS feeds all over the site so that you can subscribe to updated content. The main RSS feed is at the left of most pages in the Subscribe section. You'll also see smaller RSS icons at the bottom of many pages; they let you subscribe to a feed for that page. For example, if you click a tag for an article or story (they're at the top, preceded by "in"), you'll see all the articles and stories that have that same tag. And, at the bottom of that page, there's an RSS icon that lets you subscribe to any new articles with that tag.
Our low-volume mailing list keeps you up to date with what's going on. I just checked to see exactly how low-volume it was: there were four mailings last year. I hope we'll manage to get up to one every month or two because there's a lot going on.
There also are discussion forums for each of the major areas on the site. Feel free to participate. In order to funnel feedback into the forums, I've generally turned off the comment feature for more stories and articles--but the comments are welcome on the forums. (They were getting lost before)