I've been thinking about this for a while, and finally decided to do the jump today. Which, of course, meant there were immediate and nasty repercussions.
I've imported all my users, entries, comments, and categories into drupal. Why is a long story, and one that's likely to come out over the course of the next few days, but it's been brewing for a few months. It has had no small influence on my hesitation to post here.