Ever since Drupal 6 was released people have been wondering whether or not they should upgrade from Drupal 5. Meanwhile people who are new to Drupal wonder whether they should start their site on the 5 or 6 branch. These questions are valid. I've asked them myself. This site is built using Drupal 6 but I still have a few others on Drupal 5. Having a bit of experience using both versions I'll do my best to shed some light on which choice you should make.