These features are not available out of the box. Basically you need to create a custom module. To implement avatars the easiest way is using users profiles and custom fields for them where you can get/set the image.
Answered/open thread - you can achieve this with css and a button that sets a class to a given post. You need to create a custom table in the database to persist this value. Number of visits - this will also require custom data layer where you save the post/thread id and the number of visits. For the rss you need a custom module
that implements required interfaces.
the Telerik team
Registration for Q1 2011 What’s New Webinar Week is now open. Mark your calendar for the week starting March 21st and book your seat
for a walk through all the exciting stuff we ship with the new release!