Incident management is a light-weight modification of task management to help you handle typical help-desk communication – customer requests and inquiries. There are no analysis/implementation/verification phases, so the incidents can be processed much quicker (albeit with less control over quality of resolutions). Incidents should not be used to govern generic issues (that's what tasks are for); intended use is only for specific problems of specific customers.
The process model of incidents is simple indeed.
There are three possible states:
Project members with client role can only access incidents they either reported, own or have been added as a notifiable person for the incident; any other role gives full access to all incidents within the project.