Here is the DMV mentioned:
/*can identify all Enterprise-edition-specific features that are enabled within a user database by
using the sys.dm_db_persisted_sku_features Dynamic Management View */
--SQL Server 2008 only
USE <DBNAME>
GO
SELECT * FROM sys.dm_db_persisted_sku_features
I have this as 2008 only. I assume it will also work for 2008 R2. Maybe it was talking about the previous versions (2005 and before).