With BuddyPress Rate Forum Posts plugin your BuddyPress site memebrs can rate forum posts. It highlights good posts whereas poor posts are diminished. Highlighted karma points are visible for each site member. Note: The plugin is only for group forums, it is yet not compatible with BuddyPress site wide forums feature.
Super Post adds many useful features for displaying your WordPress blog posts and post types is a better way. The plugin is compatible with all post types and automatically adds various useful options, gives you more controls over your blog content.