Taxonomy bulk edit in Drupal 7
I don't believe there is a really easy way to do this with d7 yet. Views bulk operations will probably be your best bet for the future, as there is work going on to provide this functionality (see: http://drupal.org/node/1142062). 

In the meantime, vbo does work with the rules module, so it looks like it might be possible to use rules and vbo together to accomplish bulk taxonomy updates, although I don't think this is trivial. This screencast: http://vimeo.com/26884701 and this comment: http://drupal.org/node/1057158#comment-4792118 might help to get you started.