Contextual links is a great addition for the admin UI of any website. So much so that it has become part of the core in Drupal 7.0. It adds administrative links on nodes, comments, views... But it doesn't cover absolutely everything. What if you want contextual links for the nodes inside a view? What about views rows? That depends on your rows. It works out of the box when using the "Node" row plugin, because of the native node contextual links. If you're using field rows though, you'll have to do some hacking to get it there.