This week I had my first fun WP3.0 project using the custom post types along with custom taxonomies. They worked together to make a custom Membership Directory. I found the following plugins very helpful.
I found that the custom post type and taxonomies were pretty easy to setup and worked seamlessly. The trick is that most plugins are not setup to run on custom post types yet, so your resources currently are limited. Also since I wanted to have search capabilities for my post type and taxonomies I had to hack up the search.php file to allow for both public and private searches to function correctly and created a custom search form to allow the user to search specific fields of the record, such as searching by Name or Company or All fields, which is where the Search Everything plugin comes in handy. The searching functionality of WordPress is lacking in quality documentation. Other then having to hand hold searches the process was fairly simple.