From the CRM Resource Center, some great goodies!

• 11 Things to Know About Customization - Conceptual article aimed at system administrators, developers, people who customize CRM. This article contains links to 11 other articles in a series format. Revised for 4.0.
• Design considerations for business units - Conceptual article aimed at system administrators, people who deploy and customize CRM. This one is about structuring CRM for your business hierarchy. Revised for 4.0.
• Edit your Site Map: Configure the Site Map to customize application navigation - Combination how-to and conceptual article for system customizers, developers, and system administrators. New for 4.0.
• Close multiple activities with a workflow - Scenario-based article with how-to steps for one of 4.0’s new features. General interest. New for 4.0.
• To delete or not to delete: How Microsoft Dynamics CRM for Outlook handles deleted records - This article explains some of the behavior of CRM that causes confusion for users. It contains guidelines and 2 tables with examples. General interest. New for 4.0.

All the above articles are focused on CRM 4.0 ;)