[dsr_]

Different media have different affordances and cultures.

I happen to think:

email is for discussion with people, and occasionally for notifications/reminders

chat systems are for talking in near-realtime

Usenet is for long slow public conversations

forums are like Usenet but worse for reading

RSS is for reading periodic content - comics, newspaper articles, magazine articles, columns, blogs

Newsletters are clearly periodic content, so RSS is the way.