The signal-to-noise on twitter is too high, and I wouldn't want to subscribe to an entire board either - in both cases it's too easy to miss the announcement among all the other unrelated items.
There ought to be a dedicated channel for release announcements. It could be its own board, a mailing list, RSS, whatever - but it needs to be mainly security alerts and release notes.
Failing that, at least the update notification in the VM control panel ought to report the *latest* release, not just the *next* release.