For planned outages notify (pardon the spam-bot resistant form):
pagermonkeys (at) sf-lug (dot) com
Note that the e-mail address (alias) may be subject to change in the future.

Edit /etc/motd and/or /etc/issue as appropriate in the case of on-going fixes and updates.

Out-of-band status page? Something may be placed somewhere on/under http://sf-lug.org/ (or possibly elsewhere … still a "to be done" item).