Hello,
It got Released on 14-Jul-2011.
Please Note: Migration of Symantec Endpoint Protection Manager 11 RU7 to 12.1 will not be supported until 12.1 RU1 (Client upgrades are OK).
So, Incase, if you have Migrated to 11.0.7000, and then you have decided to Migrate to SEP 12.1, then you would have to what for some days, till next release of SEP 12.1.
Check this Articles:
1) Upgrading and migrating to Symantec Endpoint Protection 12.1
http://www.symantec.com/docs/TECH163602
2) Support for Migrating from Endpoint Protection 11 Release Update 7 to Endpoint Protection 12.1
http://www.symantec.com/docs/TECH163698