Dries predicted that there will be at least 10 books about Drupal published in 2008. Good news, he might've been right.
After Drupal 5 Themes (which, I know, was released in december last year) Packt Publishing just released two new books:
There's reviews to these books coming these days.
Also Packt will be releasing Learning Drupal 6 Module Development in June and O'Reilly a Drupal cookbook.
