Just noticed that the Fantastico installer on Bluehost has just been upgraded to offer Drupal 5.1.
Ironically, I recently trashed my Drupal 4.6 installation on Bluehost and manually installed Drupal 5.1 myself. This was because I was eager to try Drupal 5.1 out and didn't anticipate Fantastico making 5.1 available so promptly. Also, I wanted to try out the installation process myself and be a little more in control of my own destiny.
I was also concerned whether the automated 4.6 to 5.1 upgrade would be completely error free.
I agreed with the sentiments in this article about security and tracking the latest release. Having said that, I think it is good for Drupal and Bluehost customers to have easy access to Drupal 5.1.