64 Bits are Overrated

"I think they are doing a marketing gimmick. There's zero benefit a consumer gets from that. Predominantly... you need it for memory addressability beyond 4GB. That's it. You don't really need it for performance, and the kinds of applications that 64-bit get used in mostly are large, server-class applications." -- Anand Chandrasekher

most desktop apps never use more than 1 gigabyte of memory (mostly due to the von-neumann bottleneck). And 32bit still allows using more than 4 gigs of memory:
http://en.wikipedia.org/wiki/Physical_Address_Extension

So basically 64 bits just waste transistors.

>>8

64bits are really about per process memory, and even then 32bit x86 can still utilize 64bit address bus using segments and far pointers. But no, you have to waste 2x memory on 64bit pointers everywhere.