What are advantages of 64-bit system in relation to SQL Server?

We have most of our database systems on 64-bit environment, but one of the application user asked the question what is the advantage of a 64-bit environment in relation to SQL Server application. I would say with the evolution of SQL Server 2005 it has opened many more differentiation between 32- and 64-bit editions and bit hard for the application to deploy the 64-bit edition among those who would benefit most from it. Basically if your database system such as Data Mining or Data Warehousing application...(<a href="http://sqlserver-qa.net/blogs/x64/archive/2007/12/19/2986.aspx">read more</a>)<img src="http://sqlserver-qa.net/aggbug.aspx?PostID=2986" width="1" height="1">