Keeping track of all the versions and editions SQL Server instances can be a daunting task if you don’t have the right tools and documentation. A very easy way to obtain version, edition and build information from your SQL Servers is by querying the SERVERPROPERTY function as follows:

SELECT
SERVERPROPERTY(‘Edition’) AS ‘Edition’,
SERVERPROPERTY(‘ProductVersion’) AS ‘ProductVersion’,
SERVERPROPERTY(‘ProductLevel’) AS ‘ProductLevel’,
SERVERPROPERTY(‘ResourceLastUpdateDateTime’) AS ‘LastUpdate’, SERVERPROPERTY(‘ResourceVersion’) AS ‘Version’

Additional info: http://support.microsoft.com/kb/321185