How to know if SQL 2008 DB is using 2008 features that are not in SQL 2005 ?

Hello is there a way to find out if a SQL 2008 DB is using new SQL 2008 features/settings that don't exist in SQL 2005 ?

And then the other way around if it's possible to get a list of all items in SQL 2005 that are deprecated/unsupported in SQL 2008 ?

Thanks in advance.