'new comments' block

A new comments block in the /stream page wouldn't go amiss, and might go some way to address #1258716: Activity items do not include comments made on nodes.

I accomplished this with this query_alter:

function nodenewcomment_views_query_alter(&$view, &$query) {
  
  if ($view->name == 'new_comments') {
    foreach ($query->where[0]['clauses'] as &$clause) {
      if (strstr($clause, 'last_comment_timestamp')) {
        $clause = 'history_user.timestamp < node_comment_statistics.last_comment_timestamp';
      }
    }
  }
}

This could also be extended to be group-context sensitive or to only include comments in nodes which a user has posted on, using the relevant filters.