WordPress with non-MD5 Passwords
Yes, WordPress is using phpass for users's passwords, but you better change the second parameter to the call of PasswordHash from TRUE to FALSE in the file wp-includes/pluggable.php to get non-MD5/improved hash algorithms.
The algorithm is referenced in the hash stored in the database, so you should be able to change this parameter in every direction while leaving the logins active.
If you change the call to PasswordHash, you also need to set a new password, to propagate the chanes.
Tag Cloud Bugs
Mind the tag cloud on my site, it lacks reliability in the moment, e.g. try O!Play in the Tag Cloud and compare the results with a search for the same word.
Drupal to WordPress Migration
Since I wanted to downsize my application to simple blogging and the advantages of the updating process impressed me, I am now preparing the switch from Drupal 6 to WordPress 3.
After the SQL-based content migration and testing on an internal site, it's now live on http://shellack.de/blog.