3. Using personal contact lists on Nexus
In the section on searching the GAL we mentioned that when you open Address Book and select your Nexus account from the list of groups in the left hand pane you will see not only the 'Exchange Global Address List' (under 'Directories') but also 'Contacts' under 'Exchange': this 'Contacts' list is your personal address book stored on the Nexus server.
You can create and manage personal contact lists on Nexus in exactly the same way that you have always created and managed your locally stored contact lists in Address Book. The only difference is that if you store your personal contact lists in Address Book on Nexus they will be available to you however you are accessing Nexus. For example, if you are away from your computer and are accessing Nexus via OWA (the web interface) you would still have access to the personal contact lists that you created in Address Book under your Nexus account.
In summary, unless you specifically want a personal contact list to be only visible on your computer, it makes sense to store contacts on the Nexus server so that they are available to you however you are accessing Nexus.