Form Assistant leaves Appointment
Organizer field blank

This appears to be a bug in MS CRM 3.0.  In a Lead, if you click on Follow up to show the Form Assistant, then create an appointment, the appointment will have its Owner set to the chosen user (current user by default) but the Organizer field will be left blank.  And until you also set the Organizer field, the appointment will not show on the CRM calendar for the user.

A fairly simple workaround is to create a Workflow rule that fires whenever an Appointment is created and checks to see if the Organizer field is NULL and if so, sets it to the Owner of the Appointment.

You can import this Workflow rule using the Microsoft CRM Import Workflow Wizard from this file: CRMWorkflow.SetAppointmentOrganizerToOwner.xml