during the process to add a new feed (control+N), you have a possibility to check a checkbox to mark feeds that comes from discussion forums... somthing like "Is this a discussion forum?"

after the new feed added with this checkbox marked, the right side panel, would group the messages that comes with the same subject with a "+" at the begining of the line (by clicking it would expand to all messages or collapse) .... this would be very useful for people that follow multiple forums topics thru rss...

+ This is a group topic from...            (parent topic, level 1 indent )

     |_ This is a group topic from...      (child topic, level 2 indent )

     |_ This is a group topic from...      (child topic, level 2 indent )

     |_ This is a group topic from...      (child topic, level 2 indent )

of corse this is just a suggestion and should be many other ways to accomplish this easyer but with or without this suggestion... as always, amazing job done here !