Sorry for necro-posting.
But nothing seems to have happened in 6+ months?
It is still not possible to create a stream that shows a list of topics (only topics, not individual posts) with new content since my last visit.
With the amount of traffic and content we receive having the same topic show up in the stream each time a member posts in it, destroys the overview of the AS and makes it useless.
Are there any plugins out there that creates the functionality where I get a "list of topics with new posts since my last visit, where each topic only shows once even if 50 people posted new replies in it"?