As to the root issue (advertising community SSU to comparatively passive N8x0 users), the original hope when we first floated the idea of a community SSU would be that Nokia would ship an update which enabled the repo, installed the trust keys and package domains and then users would start getting updates from the community.

If someone isn't actively following maemo.org, there's nothing we can do (those of us here) to get users to install a packge to enable community SSU. Unfortunately, the only people who can do that are Nokia's Diablo team...