I have been testing Change Management in System Center Service Manager beta 1.

ITIL defines the change management process this way:

The goal of the Change Management process is to ensure that standardized methods and procedures are used for efficient and prompt handling of all changes, in order to minimize the impact of change-related incidents upon service quality, and consequently improve the day-to-day operations of the organization.

Change management is responsible for managing change process involving:
* Hardware
* Communication equipement and software
* System Software
* All documentation and procedures associated with the running, support and maintenance of live systems

Source: en.wikipedia.org

System Center Service Manager has a connector to System Center Configuration Manager that synchronizes hardware information and other relevant information to Service Manager. When creating a change request it is possible to pick/select objects syncronized from Configuration Manager. For example if you want to create a change request, regarding a security group in Active Directory, then you can select the group from the list. You can also open the object direct from the change request form, that is a convenient method when you need to verify some information.

 
Another alternative to start a change request is to select a object and then click create change request from the task bar. Then related items are already filled in. In the example below we want to create a change request involving Vista Service Pack 2.

 

When creating a new change request there are a couple of templates delivered out of the box. It is possible to create your own templates with pre-defined attributes like area, priority, people to notify, risk level and impact.

On the Related Items tab, of the change request, the creator can add related items like objects from Configuration Manager, Active Directory, documents and files and other work items. Work items can be for example incidents that are related to this change request. 

When a change is submitted the creator can track the change request on then process tab.

 

When all activities are carried out and the change request is filled in you can close the change request from the console.

It is possible to configure notification to get notified when something is happening. For example if someone creates a new change request you want to send a notification to all change reviewers.

It is reasonably easy to configure change management templates and notifications based on them. But it is a number of steps to take and a name standard has never been more important. If you don’t have a good name standard you will lose yourself pretty quick. Something that I think most Operations Manager 2007 administrators recognize. There are a couple of notification scenarios where I could see a need of more detailed criteria parameters. But as this is Service Manager beta 1 I guess we will see a lot more features in later beta versions and the RTM version. I think that the biggest obstacle will not be to how to configure Service Manager but instead how to plan and design all your workflows within your organization before you can input them into Service Manager.

If you are interesting in change process flow there is a lot of good information here at TechNet.