'is there a tangible development plan for the moodle forums?'
Based on the discussion it seems not. But there does seem to be people with ideas, and some with solutions.
So I guess the next question is:
How to move this forward? - should we be looking to simply update the current forum tool with the advancements in forumNG, Advanced forums and other developments or look to build a new tool that takes these factors into account plus adds some best practice functionalities from forum(esq) tools from the web.
PS. We're meeting with Catalyst IT later this week to discuss the technicalities of the 'reading list' functionality, perhaps when we have a technical design we can post here for comment/discussion.