Maybe this sort of thing could be added to topics, effectively allowing for a more of questions and answers time app. Basically allowing a user to vote on good answers inside a topic? maybe its slightly different outcome because of course you dont want to change the order of the answers to a topic but maybe you want to list topics by what is hot so to speak.
@rastin yes thats probably a more fitting way. I actually like the new structure of just topics and the removal of say traditional discussion rooms. The ultimate idea I guess is the following:
To be able to use a global search to search for say "what is the best coffee shop in london". Of course you will get few topics on this (if your site is geared towards this), so to be able to filter by likes would be great but I guess the replies in this example matter too. Due to the fact there just might be a reply to one of the topics that is very popular with likes and could be a great answers. I know questions and answers type apps like Quora have a slightly different thought process than say a discussion forum.
But freshness and most popular is a logical start for sure:)