No Gail - its not: "sys.dm_db_persisted_sku_features" is not supported in 2005. However I foudn an excellent article located here:
http://www.trycatchfinally.net/2013/04/identifying-sql-server-2005-enterprise-edition-features-in-use/
that has a script that checks for enterprise features being used. I have included it below for reference:
select * from
(-- VarDecimal Storage Format
select case
when max(objectproperty(object_id, N'TableHasVarDecimalStorageFormat')) = 0
then ''
else 'VarDecimal Storage'
end as feature_name
from sys.objects
UNION ALL
-- Partitioning
select case
when max(partition_number) > 1
then 'Partitioning'
else ''
end
from sys.partitions
) t
where feature_name <> ''