The settings that are migrated are :
1.AntiVirus and AntiSpyware policy
2.scheduled scans
3. LiveUpdate4
4. Quarantine purge
5.exclusions
Are exclusions migrated?
Yes. During migration, when you select to inherit settings from the server group or parent management server, those exclusion settings are migrated to centralized exceptions in the Symantec Endpoint Protection Manager console. If you migrate clients individually by running the installation on the local client, client exclusion settings are not migrated.
Tamper Protection settings are not migrated. Tamper Protection settings are included in the client general settings rather than the AntiVirus and AntiSpyware policy. Also, you must reconfigure the settings that you disabled for migration, such as scheduled scans, LiveUpdate, and Quarantine purge.
Previously, migrating to newer versions of Symantec AntiVirus required a full product installation, which stressed bandwidth limitations over WAN links.
http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2007071909500548