Hey Karthik 2.0,
No how is 64-bit mode different from 32-bit mode!
Although the usage of 64-bit registers is very nice, it won't make your PC fly significantly faster unless not only the operating system but also the _applications_ are compiled into 64-bit executables!
However, CPU companies _must_ sell 64-bit CPU's already - even if it doesn't make sense - because that's the only way of winning back the investments, thus making the technology cheap. _Then_ will 64-bit CPU's be available in large quantities, at higher clock rates, for sensible prices and at _then_ will this be useful for people, especially gamers.
But, c'mon, 64-bit CPU's into desktop PC's, for the average secretaries? After having done 64-bit multiplication and division in 16-bit assembly and 32-bit SQL, I find this hype quite ridiculous...
Joe