I thinks a Mother Board that handles 64 (high level level transactions ONLY) on a dual Socket Motherbard would be an easy way to let consumers actually SEE what 64 bit functions were actually being utilized would be the rational way to market 64 bit systems, if your chip is providing any benifit.
However 64 bit chips though possible are a need that is being manufactured through advertizing and marketing. That you would buy chips too simply serves to subsidize the needs of Corporations with your money.
It's like buying your master a new chain to tie you up with.
No matter how intelligent computers may be, they will never have ethics.
The real question is, will you?