I run a hosting company that particularly specializes in Drupal. I ask this partly for my own benefit, and partly for any other host that is doing Drupal support -
What are you looking for in a Drupal hosting company?
What are your main gripes about Drupal hosting?
Please don't get into a diatribe or praise of a particular host - I'm actually looking for a sense of what the community is looking for, scince I don't think we very often ask the question.