TLC - How do you manage communications?
Expert 
I am looking for advice and experience on how to manage the following types of communications:
Uptime/downtime notifications for routine planned maintenance
Uptime/downtime notifications for unplanned maintenance/events
Product update information (service pack updates and new releases both major and minor)
Informational updates that include webinars, on-line training, and other events led by the CS team.
I am thinking of using a Trust site and subscriptions for the first two and possibly routine updates. I think major releases need more and a combination of subscriptions, email campaigns and in-application updates. Informational updates might be subscription based with an opt out option.
What do you do? Advice/experience appreciated.