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 will take utmost advantage from a 64-bit platform. For me nothing is different between 32 or 64 bit systems, as in X64 it is only memory advantage. The Development team within Microsoft compiled and optimized the 64-bit edition specifically to run on a 64-bit Windows Server which is default requirement of having 64-bit processor. So having a system such as SQL Server 2005 (and Windows Server 2003 or going to Windows Server 2008 in next year) both run on the 64-bit x (Intel/AMD) and the Itanium (Intel-only) platforms. So here the important part is played by the hardware to take such an advantage of performance with huge-pool of resources and as said itis the first main advantage 64-bit provides for SQL Server is the ability to directly deal with larger amounts of memory.

In relation to the advantages list I would like to refer the documentation about the advantages of 64-bit environments for SQL Server which relates to the  AP's Advance Planning and Optimization with SQL Server. As referred above Analysis Services (OLAP based applications) can be one of the most memory-hungry applications around, especially if you're working with databases several gigabytes in size or processing data cubes with many dimensions. Now the consolidation of servers is an important bit within the Organisations, so having such restricted compatability using 64-bit server will reduce the memory barriers that existed before are gone, these apps can run side by side on the same machine and still show off a boost in performance that they couldn't have before, don't take it granted and always test your applications in real-time.

As 64-bit is huge-pool of memory having large number of concurrent users to the application is no more a problem, with this more physical memory that can be addressed, the greater the number of concurrent user connections can be sustained without breaking a sweat. So if you have been asked to migrate to 64-bit do not hesitate to say 'YES' as such a migration of environment to the 64-bit SQL Server will still require a good deal of planning and work. Not to mention about ETL process completion, using the legendary DTS methodolog system from SQL Server 2000 and before has not been ported to 64-bit environments. SSIS is a replacement for DTS and will work with SQL engine within a 64 bit application that will be significantly more powerful and flexible. So it is better to get more practice with SSIS so these packages can be converted or rewritten before the 64-bit leap.