We need experienced developers that specialize in or are highly involved in the Drupal community. A minimum of 2 years experience working with Drupal professionally is needed. Most of the candidates we've seen so far have only worked occasionally or non-professionally with Drupal.
Good indicators:
Full profile on drupal.org (example: http://drupal.org/user/1312756 )
Drupal focused resume with several projects in Drupal
Links to several (publicly accessible) sites built in Drupal
Experience on a large Drupal focused team (such as Sony Music, NYSE, Economist, Martha Stewart)
Experience at a Drupal focused agency (such as Acquia, Lullabot, DPCI, Four Kitchens, Zivtech)
Bad indicators:
No profile or empty profile on drupal.org
Drupal only mentioned on one or two projects