The official @Directory_Opus account on Twitter will post about new versions of Opus and similar major announcements.
There is also a Directory Opus News blog to give you a convenient way to receive Opus-related news (e.g. using an RSS reader).
If you regularly read the forum then the Twitter account and news blog will probably be redundant; they exist for people who don't have the time or interest to keep up with the forum but still want a low-volume feed of announcements.