Ah. Silly me. I experimented with the drupal caching options just before installing the WYSIWYG module and wondered why the editor was not showing up.

The solution was as obvious as simple: I had to disable or clear Drupal's JavaScript and CSS cache after installing the WYSIWYG plugin.

Hopefully you read this before long searching. Additional clues can be found in this drupal forum post ( http://drupal.org/node/426398 ).