I had a discussion on that when I was @IT FORUM.
Ofcourse 64 bit will perform better I fully agree, but most of the time
people just forget to optimize their databases, actually no one looks at how
their queries perform, how they can be optimized, especially when using some
customized ERP or CRM applications that used to have their own storage
engine and now support sql server as the backend storage
MCSE, MCSA, MCDBA, MCT